Knowledge (XXG)

:Reference desk/Archives/Mathematics/2010 February 23 - Knowledge (XXG)

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1901:
your second statement? Likewise, if you take any function f from A to B and restrict the codomain of the function to the image, then that new function is surjective. Are we still chasing each other in circles here? Rereading you question 3 outdents above, yes, saying that f is a surjective function from A onto C gives you item 2. but does miss item 1. Saying that f is a bijection from A to C gives 1. (because bijection implies injection) but it also gives you 2. (because bijection implies surjection). (Note the comment in my previous reply about the ambiguities of
1260:) has no impact on the characteristics (injective, surjective, bijective, etc.) of a correspondence or function. As Meni Rosenfeld stated above, a function is defined by its domain, its range, and a rule mapping between them; changing the domain or range can change characteristics of the function because it means defining a new function, even it that new function seems a natural extension of the old one. Likewise a correspondence between sets 455:
in each) so can anyone please point me to a good resource on the internet that I can use to write my own source code. Something fast and efficient preferably. If somebody has an m file laying around that already does this or if someone known how to do this on MATLAB for example, it would be appreciated. This is just one of the steps in a larger scheme. Oh and I also have an irreducible polynomial given as the modulus. Thanks!
3354: 2101:(←)So I believe that I do get a sense of where your unease originates, but I think that with precise language no contradiction appears. I have reread this section, and I believe that all your questions, as stated, are properly answered "bijection". So can you precisely restate your problem with a well defined function or relation? I suggest that for clarity we stick with terms such a 2982: 3905: 1947:
I don't accept your first assumption, because changing the codomain may change the image. For example, when the domain is the set of positive numbers, and F(x) is defined to be the number whose absoloue value is x, then the image of F is the set of positive/negative numbers - when the codomain is the
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I thik they probably duplicated the 3 in the second number. Perhaps this is some sort of alien maze test on the reference desk to see how it scurries around when presented with random stuff? I've noticed mopre and more of these type questions where they just enter some random search query with random
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Hello, for a computer science project, I am looking for an algorithm that will invert any given element (zero maps to zero) in the Galois Field GF(2^128) and give me its multiplicative inverse. The problem is that my background in abstract algebra/number theory is very limited (one undergrad course
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What is your question? Any calculator will give you a value of about 0.8. Are you wondering why there are two 3's in the denominator? Are you wondering what / means? Are you wondering why your computer didn't instamagically speak the answer to you when you randomly typed numbers into some random
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is currently blowing my mind -- although my friends are less impressed having apparently learned it in grade school. At any rate, what is the proof that it works? Also, I see that it can be generalized to nth roots, when n is an integer -- which lets you calculate nth roots when n is rational -- is
2413:
Now when we say a function from X to Y we mean just like what 58.147.60.130 said; it's an ordered triplet (X,Y,G), where G is a subset of XxY that's a function. Such a function is said to be a bijection if it satisfies the condition I mentioned above. If it helps you can think of when the phrase "A
1900:
Do you agree that if f is a bijection (or even just a surjection) from A to C then then C is the image of any function f redefined by simply changing its codomain? (The codomain of a function is always a superset of its image.) If so, then doesn't saying that f is a bijection between A and C give
1861:
You've replied to an old version of my question. I'd changed my question before you answered (but after you saw the old version). Please review my question again. Anyways, If I simply say that F is a bijection between A and C (or is an injection from A to B, or to C), then I miss the second
3349:{\displaystyle {\begin{aligned}e^{x}&=\left^{x}\\&=\lim _{n\to \infty }\left^{x}\\&=\lim _{n\to \infty }\left(1+{\frac {1}{n}}\right)^{nx}\\&=\lim _{n\to \infty }\left(1+{\frac {x}{nx}}\right)^{nx}\\&=\lim _{m\to \infty }\left(1+{\frac {x}{m}}\right)^{m}.\end{aligned}}} 2070:) and 2. it is not functional (2 inv_abs 2 and 2 inv_abs -2). If we restrict the domain to the positive reals (as you suggested) it becomes left-total. If we then restrict the codomain to either the positive reals or the negative reals it becomes functional and is in fact a bijection. 3606: 2414:
and B have the same cardinality" as a relation between sets, rather than a function. So when we change the codomain Y to Z, we must make sure G is still a subset of XxZ and is still a function. In actually defining G we use a formula like what Rosenfeld said.
2004:
There is a slippery semantic slope (one that I may have already crossed) to beware of when speaking of redefining a function by changing its domain or codomain, because, as Meni Rosenfeld pointed out, they are integral to the definition of the function. (See
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Where the last step is substituting m = nx. The first step can be justified by continuity of exponentiation, and the last step is only justified if we recognize that the limit is taken over the entire real numbers, as opposed to just over the integers.
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For every x in X, there's an order pair with x as 1st coordinate, for any two ordered pairs w,t in C, if they have the same first coordinate then they have the same second coordinate (these two conditions guarantee that it's a function, not a
1955:
To sum up, if I simply say that F is a bijection between A and C (or is an injection from A to B, or to C), then I miss the information that when the domain of F is taken to be A, and the codomain of F is taken to be B, then the image of F is
3574:
The square root of 5.23 was just an example. Actually, I question was inspired by how calculator's are able to evaluate roots, which I believe is through a Taylor series. Is there a way to write a taylor series for the expression (a+x)^1/2?
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You could also divide the operand by four first: the square root of 5.23 is equal to the product of the square root of four (2) and that of 5.23/4 = 1.3075. In that case, the x in the Taylor series is 0.3075, so that would converge.
4052:
Just curious, but is there any way to show that a particular function, such as the one given here, has no elementary antiderivative, or is it simply a matter of not being able to come up with one using know methods if integration?
1113: 2009:) When I spoke of redefining the codomain I was implying that both the "before" and "after" codomains were subsets of some larger codomain where we had still defined a function, but as you point out this need not be the case. 2987: 1505:, and it is all the same function. Were you to expand the domain and range onto the reals, then using the first two rules would give you a bijection; using the third rule would not. This does not change the fact that 1172:
belonging to B may indeed be correspondent (by the inverse correspondence) to many elements, of which one single element only - is in A, or: does the phrase "one to one correspondence between A and B" mean that every
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For every w,t in C, if they have the same second coordinate then they have the same first coordinate (this is for injection). For every y in Y, there's an ordered pair in C with y as second coordinate (this is for
3900:{\displaystyle {\sqrt {N^{2}+d}}=\sum _{n=0}^{\infty }{\frac {(-1)^{n}(2n)!d^{n}}{(1-2n)n!^{2}4^{n}N^{2n-1}}}=N+{\frac {d}{2N}}-{\frac {d^{2}}{8N^{3}}}+{\frac {d^{3}}{16N^{5}}}-{\frac {5d^{4}}{128N^{7}}}+\cdots } 4811:
You could just approximate n by a rational r, and then compute the rth root. If you're going digit-by-digit then just make r so close to n that the rth root and the nth root match at the digit you're computing.
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belonging to B is correspondent (by the inverse correspondence) to many elements, of which one single element only - is in A, or: does the phrase "one to one function between A and B" mean that every
2330: 55: 51: 4396: 956:. Usually it is understood that the domain is implicitly specified to be the largest domain possible for the expression, but in your question this seems to be a source of confusion. The function 1386: 59: 670: 4452:
It's easy to see why this is true, but for a rigorous proof you need to be careful with respect to the decimal point (and perhaps some induction). It boils down to having a current guess
740: 705: 596: 526: 2627: 1503: 2237: 3979: 199: 4792: 4561: 1589:(i.e. the information that when the domain of F is taken to be A, and the codomain of F is taken to be B, then: for every a,b belonging to the domain of F, if f(a)=f(b) then a=b) 4618: 3478:
How would I be able to approximate a square root, like (5.23)^.5, with a taylor series. I know the Taylor series for (1+x)^(1/2), but that only converges for 0<x<1...
1729: 1450: 1418: 4503: 2548: 950: 1300:. There may be what seems to you a natural extension of the correspondence to a larger universe, but that is immaterial for considerations of the correspondence itself. 4731: 2370: 2350: 1703: 1671: 4693: 4651: 1137:
By "bijection" I meant "one to one correspondence". I'm unnecessarily talking about a function, although every one to one function is also a one to one correspondence.
25: 3508:| < 1. The convergence will be slow though. Why do you want to do it and why is using the Taylor series important since most any calculator will give the result? 1809: 1789: 1769: 1749: 1523: 1641:
I am trying, but no, I am not seeing your problem yet. For a function to be bijective is equivalent to it being both injective and surjective. So saying that
4116: 2388:". This looks like a short way to describe it, but any shorter one will depend on a convention for denoting the induced relation, of which I am not aware. -- 1587:
Do you see now my problem? If I simply say that F is a surjective from A onto C (thus informing that C is the image of F), then I miss the first information
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A correspondence, as well as a one to one correspondence, must have a domain of discourse. In our case, the domain of discourse is the set of real numbers.
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The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the
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Given two sets X and Y, we say they are one to one correspondent if there's a subset C of XxY (cartesian product) such that the following are satisfied:
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with its original domain and range is bijective if defined by any of the the three rules, because with that original domain the rules are equivalent.
474:. If you want highly optimized code, web search on "finite field inversion". A huge amount of work has been done to optimize that operation, for 1551:
Let's put it this way: F is a function, and A,B,C are sets. Is there a simple phrase expressing the following two pieces of information (at once)?
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belonging to A may indeed be correspondent (by that correspondence) to many elements, of which one single element only - is in B, and that every
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information, i.e. the information that when the domain of F is taken to be A, and the codomain of F is taken to be B, then the image of F is C.
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I don't think it can be generalized to irrational-order roots in any meaningful way. Using exp and log is the way to go for general powers. --
1591:. However, if I simply say that F is a bijection between A and C (or is an injection from A to B, or to C), then I miss the second information 2893: 4229: 21: 4437: 4086: 4054: 3917: 3485: 2445: 2158: 2071: 1906: 1828: 1526: 1329: 1301: 529: 479: 456: 342: 115: 959: 4426: 3580: 3560: 3539: 1593:(i.e. the information that when the domain of F is taken to be A, and the codomain of F is taken to be B, then the image of F is C) 2702: 2633: 4821: 4806: 4445: 4411: 4338: 4319: 4094: 4080: 4062: 4047: 4029: 4010: 3990: 3925: 3592: 3568: 3551: 3532: 3517: 3493: 3466: 3439: 3367: 2852: 2776: 2453: 2423: 2397: 2166: 2079: 1967: 1914: 1871: 1836: 1620: 1534: 1337: 1309: 1239: 1128: 908: 753: 537: 487: 464: 444: 419: 392: 373: 350: 155: 123: 3376:
1. Prove that for all real x the sequence (1+x/n) (n a positive integer) is eventually increasing; precisely, as soon as n: -->
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Also, when you write "correspondence", do you mean a "binary relation that is both left-total and right-total" as defined in
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by Boris A. Kordemsky presents the following four numbers, each of which is an arrangement of the ten digits 0 through 9:
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Ooh okay, didn't see that article. But one last question (to make sure that I understand Taylor series), is the equation
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One sometimes sees it mentioned that 123456789 × 8 = 987654312, just because the pattern in the digits is amusing.
625: 334:{\displaystyle \lim _{b\to \infty }{\frac {1}{b-2}}{\frac {\sum _{n=1}^{b}nb^{n-1}}{\sum _{n=1}^{b}nb^{b-n}}}=1} 4802: 4076: 4025: 3986: 3547: 3451: 2419: 2393: 1124: 710: 675: 566: 496: 2554: 4106:
You don't need to do numerical integration just because there is no elementary antiderivative. You may use a
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because if Ln(k^2) is a number belonging to the domain of discourse then k is unnecessarily a positive number
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Each of these numbers is divisible by 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, and 18. —
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The same question may be asked about a "one to one function between A and B": Does it mean that every
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although when Ln(k^2) belongs to the domain of discourse then k is unnecessarily a positive number
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need the extended Euclidean algorithm, this time for integers. But these two are separate issues.—
4817: 4330: 4039: 3524: 3359: 1708: 1423: 1391: 436: 384: 4733:(up to the decimal point). Since you want only one digit at a time, you take the greatest digit 4463: 3402:
5. Use 4 to prove exp(x)exp(y)=exp(x+y) for all x and y, which justifes the notation exp(x)=e.
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there any way to generalize again so a similar method can produce roots for any real number?
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My question is about how to interpret the phrase "one to one correspondence between A and B".
4660: 4623: 3461: 3434: 152: 4399: 4035: 3981:. Anyway, an excellent and simple way to compute square roots is the Babylonian method. -- 854:(belonging to the domain of discourse) is correspondent - by the inverse correspondence of 4068: 2006: 1325: 1253: 750: 415: 4220:{\displaystyle \int e^{\sin x}dx=\int \sum _{n=0}^{\infty }{\frac {(\sin x)^{n}}{n!}}dx=} 364:
keywords as if querying google. I think the answer is they should enter it into google.
4403: 4311: 3588: 3513: 2872: 2437:∞, but from this definition how one arrive at the equation e^x=lim(1+x/n)^n as n--: --> 1268:
does not depend on the larger universe. So when you speak of a correspondence between
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is surjective. (I doubt that this is the problem, but you do know, don't you, that a
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belonging to B is correspondent (by the inverse correspondence) to one single element
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belonging to B is correspondent (by the inverse correspondence) to one single element
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is increasing and bijective, define the inverse to be log(x) ("natural logarithm").
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is not a bijection between the set of positive numbers and the domain of discourse,
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2. Prove that it is bounded (just observe that 0≤(1+x/n)(1-x/n)≤1 as soon as n: -->
2862: 1959: 1863: 1612: 1231: 900: 672:, not for integers) does. In order to implement it, you have to do computations in 1108:{\displaystyle g:\mathbb {R} \backslash \{0\}\to \mathbb {R} ,x\mapsto \ln(x^{2})} 164:
Perhaps it was a typo and the OP meant to ask about the progress of the sequence 1
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antiderivative. You can still calculate definite integrals of it numerically. --
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It seems what HOOTmag has in mind is not a function or a relation, but rather a
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is really a bijection between the positive numbers and the domain of discourse,
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I have a technical question about either option which will turn out to be true:
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belonging to A is correspondent (by that correspondence) to one single element
4329:...and then evaluate the sums numerically? Seems to me it's still numerical. 4107: 747: 411: 771:
a bijection between the set of positive numbers and the domain of discourse?
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A calculator almost certainly would not use the Taylor series. That article
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Does the phrase "one to one correspondence between A and B" mean that every
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Consider your inverse absolute value binary relation on the reals so that
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is a bijection satisfies both your 1. and your 2. What am I missing? If
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by itself is not a function. To define a function you need to specify its
2150: 1952:. Hence, the image is dependent on the codomain (not only on the domain). 1559: 2062:). This is not a function because 1. it is not left-total (there is no 2955:{\displaystyle e=\lim _{n\to \infty }\left(1+{\frac {1}{n}}\right)^{n}} 2145:
unless we specifically define them here. (I have been guilty of using
622:, and that's what the extended Euclidean algorithm (for polynomials in 4302:{\displaystyle \sum _{n=0}^{\infty }{\frac {\int (\sin x)^{n}dx}{n!}}} 764:
Let's assume that our domain of discourse is the set of real numbers.
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Woah, that works for all finite fields? I thought it only worked for
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No, the terms of the sum involve only the elementary antiderivatives
3377:-x (use the inequality between the arithmetic and geometric means). 3500:
Well you can always approximate the square root of the inverse of
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For every a,b belonging to the domain of F, if F(a)=F(b) then a=b.
1029:{\displaystyle f:(0,+\infty )\to \mathbb {R} ,x\mapsto \ln(x^{2})} 79:
Welcome to the Knowledge (XXG) Mathematics Reference Desk Archives
3523:
You might expand about the point 5.29 = 2.3 rather than about 0.
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You can also calculate antiderivatives of it numerically. E.g.
2973: 2765:{\displaystyle =\lim _{n\to \infty }(1+{\frac {x}{nx}})^{nx}} 4427:
Methods_of_computing_square_roots#Digit_by_digit_calculation
2691:{\displaystyle =\lim _{n\to \infty }(1+{\frac {1}{n}})^{nx}} 1054: 3427:
8. Prove that exp(x) is the sum of the exponential series.
2831:{\displaystyle =\lim _{m\to \infty }(1+{\frac {x}{m}})^{m}} 785:
numbers and the domain of discourse, because for every two
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If you just want a straightforward implementation, use the
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2,438,195,760; 4,753,869,120; 3,785,942,160; 4,876,391,520.
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exp(x) to be the limit of (1+x/n) as n tends to infinity.
2438:∞. I've googled it, but couldn't find a proof anywhere. 3583:
says calculators would normally do it via log and exp.
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On the other hand, if the second option is correct, and
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In 5 it should be exp(x+y)=exp(x)exp(y), of course. --
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I have seen e defined as limit of (1-1/n)^n as n--: -->
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is a number belonging to the domain of discourse, then
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then amounts to computing an inverse polynomial modulo
4353: 610:, you add them as usual, and you multiply them modulo 4743: 4701: 4663: 4626: 4569: 4511: 4466: 4352: 4232: 4119: 3938: 3609: 2985: 2896: 2779: 2705: 2636: 2557: 2468: 2358: 2338: 2325:{\displaystyle \{(x,y)|x\in A,y\in B,\varphi (x,y)\}} 2253: 2182: 1797: 1777: 1757: 1737: 1711: 1679: 1647: 1511: 1458: 1426: 1394: 1358: 1042: 962: 919: 713: 678: 628: 569: 499: 202: 3504:
and then invert again as the series converges for |
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Also, I suggest you the following alternative path.
858:- to a single number, and this number belongs to A? 881:, and whose image is the domain of discourse (i.e. 808:does not seem to be a bijection between the set of 4786: 4725: 4687: 4645: 4612: 4555: 4497: 4391:{\displaystyle \scriptstyle {\int (\sin x)^{n}dx}} 4390: 4301: 4219: 3973: 3899: 3348: 2954: 2830: 2764: 2690: 2621: 2542: 2364: 2344: 2324: 2231: 2007:Binary relation#Is a relation more than its graph? 1803: 1783: 1763: 1743: 1723: 1697: 1665: 1517: 1497: 1444: 1412: 1380: 1107: 1028: 944: 734: 699: 664: 606:to consist of all polynomials of degree less than 590: 520: 333: 1326:Binary relation#Special types of binary relations 830:On one hand, if the first option is correct, and 425:As long as we're on this topic, this one's cute: 3291: 3223: 3160: 3085: 3014: 2904: 2784: 2710: 2641: 2562: 2486: 885:is on the range), so that for every two numbers 812:numbers and the domain of discourse, because if 204: 3540:Methods of computing square roots#Taylor series 781:does seem to be a bijection between the set of 1381:{\displaystyle f:\mathbb {Z} \to \mathbb {Z} } 8: 2319: 2254: 1063: 1057: 665:{\displaystyle (\mathbb {Z} /p\mathbb {Z} )} 4425:The method for calculating square roots at 2976:display look better by doing it like this: 1115:is not. They are both surjective, and thus 850:and the domain of discourse, so that every 707:, and in particular to compute inverses in 3384:3. Therefore it converges for any real x: 735:{\displaystyle \mathbb {Z} /p\mathbb {Z} } 700:{\displaystyle \mathbb {Z} /p\mathbb {Z} } 591:{\displaystyle \mathbb {Z} /p\mathbb {Z} } 521:{\displaystyle \mathbb {Z} /n\mathbb {Z} } 4778: 4742: 4700: 4662: 4637: 4625: 4604: 4568: 4541: 4516: 4510: 4483: 4465: 4398:. This is not numerical integration like 4374: 4354: 4351: 4276: 4254: 4248: 4237: 4231: 4191: 4172: 4166: 4155: 4127: 4118: 3965: 3946: 3937: 3882: 3867: 3857: 3845: 3831: 3825: 3813: 3799: 3793: 3775: 3748: 3738: 3728: 3695: 3670: 3654: 3648: 3637: 3616: 3610: 3608: 3333: 3318: 3294: 3270: 3250: 3226: 3202: 3187: 3163: 3142: 3132: 3117: 3088: 3067: 3056: 3041: 3017: 2994: 2986: 2984: 2946: 2931: 2907: 2895: 2822: 2808: 2787: 2778: 2753: 2734: 2713: 2704: 2679: 2665: 2644: 2635: 2622:{\displaystyle =\lim _{n\to \infty }^{x}} 2613: 2603: 2589: 2565: 2556: 2534: 2524: 2510: 2489: 2473: 2467: 2357: 2337: 2272: 2252: 2215: 2207: 2181: 2157:-- a minority usage that I will eschew.) 1796: 1776: 1756: 1736: 1710: 1678: 1646: 1510: 1457: 1425: 1393: 1374: 1373: 1366: 1365: 1357: 1096: 1070: 1069: 1050: 1049: 1041: 1017: 991: 990: 961: 933: 918: 728: 727: 719: 715: 714: 712: 693: 692: 684: 680: 679: 677: 646: 645: 637: 633: 632: 627: 584: 583: 575: 571: 570: 568: 555:prime? You fix an irreducible polynomial 514: 513: 505: 501: 500: 498: 310: 297: 286: 268: 255: 244: 237: 219: 207: 201: 2972:Also, you can make "COVIZAPIBETEFOKY"'s 2332:. The question is about the property of 1498:{\displaystyle x\mapsto x\cos(2\pi x)+1} 49: 36: 65: 543:How do you represent the finite field 43: 2232:{\displaystyle \varphi (x,y)=(|y|=x)} 7: 3974:{\displaystyle -N^{2}<d<N^{2}} 1352:Note that you may define a function 4787:{\displaystyle (2p+x)x\leq S-p^{2}} 2877:Introductio in Analysin Infinitorum 2867:Principles of Mathematical Analysis 131:website that you stumbled upon? -- 4249: 4167: 3649: 3301: 3233: 3170: 3095: 3024: 2914: 2794: 2720: 2651: 2572: 2496: 981: 214: 196:, ..., specifically the fact that 32: 4556:{\displaystyle p^{2}+2px+x^{2}=S} 3581:Methods of computing square roots 2247:, the formula induces a relation 1948:set of positive/negative numbers 3454:) 16:47, 23 February 2010 (UTC) 2858:Two books you might look at are 1791:with its codomain restricted to 1731:, then saying that the image of 4613:{\displaystyle (2p+x)x=S-p^{2}} 4421:Digit by digit root calculation 1558:of F is taken to be A, and the 877:is a function, whose domain is 846:is a bijection between the set 4759: 4744: 4717: 4702: 4679: 4664: 4585: 4570: 4480: 4467: 4371: 4358: 4273: 4260: 4188: 4175: 3718: 3703: 3685: 3676: 3667: 3657: 3298: 3230: 3167: 3092: 3021: 2911: 2819: 2799: 2791: 2750: 2725: 2717: 2676: 2656: 2648: 2610: 2600: 2580: 2577: 2569: 2531: 2521: 2501: 2493: 2482: 2316: 2304: 2273: 2269: 2257: 2226: 2216: 2208: 2204: 2198: 2186: 1689: 1657: 1486: 1474: 1462: 1430: 1398: 1370: 1102: 1089: 1080: 1066: 1023: 1010: 1001: 987: 984: 969: 939: 926: 659: 653: 650: 629: 211: 18:Knowledge (XXG):Reference desk 1: 4822:14:43, 24 February 2010 (UTC) 4807:07:43, 24 February 2010 (UTC) 4446:23:04, 23 February 2010 (UTC) 4412:06:30, 27 February 2010 (UTC) 4339:18:27, 25 February 2010 (UTC) 4320:13:30, 25 February 2010 (UTC) 4095:12:01, 24 February 2010 (UTC) 4081:20:30, 23 February 2010 (UTC) 4063:19:39, 23 February 2010 (UTC) 4048:17:46, 23 February 2010 (UTC) 4030:16:44, 23 February 2010 (UTC) 4011:16:36, 23 February 2010 (UTC) 3991:07:31, 24 February 2010 (UTC) 3926:02:33, 24 February 2010 (UTC) 3593:23:06, 23 February 2010 (UTC) 3569:19:49, 25 February 2010 (UTC) 3552:13:34, 23 February 2010 (UTC) 3533:13:30, 23 February 2010 (UTC) 3518:13:07, 23 February 2010 (UTC) 3494:12:49, 23 February 2010 (UTC) 3467:20:56, 23 February 2010 (UTC) 3440:16:13, 23 February 2010 (UTC) 3368:13:18, 23 February 2010 (UTC) 2853:13:07, 23 February 2010 (UTC) 2454:12:10, 23 February 2010 (UTC) 2424:15:54, 24 February 2010 (UTC) 2398:08:30, 24 February 2010 (UTC) 2167:02:25, 24 February 2010 (UTC) 2080:02:25, 24 February 2010 (UTC) 1968:21:21, 23 February 2010 (UTC) 1915:18:48, 23 February 2010 (UTC) 1872:18:18, 23 February 2010 (UTC) 1837:18:05, 23 February 2010 (UTC) 1771:is equivalent to saying that 1621:17:35, 23 February 2010 (UTC) 1562:of F is taken to be B, then: 1535:16:01, 23 February 2010 (UTC) 1338:16:01, 23 February 2010 (UTC) 1310:15:23, 23 February 2010 (UTC) 1276:it makes no sense to talk of 1240:12:25, 23 February 2010 (UTC) 1129:09:47, 23 February 2010 (UTC) 909:09:23, 23 February 2010 (UTC) 754:11:43, 23 February 2010 (UTC) 538:07:29, 23 February 2010 (UTC) 488:07:22, 23 February 2010 (UTC) 465:07:10, 23 February 2010 (UTC) 445:23:19, 26 February 2010 (UTC) 435:(Note: 12345679, with NO 8.) 429:12 345 679 × 81 = 999 999 999 420:22:52, 23 February 2010 (UTC) 393:13:26, 23 February 2010 (UTC) 374:12:07, 23 February 2010 (UTC) 351:06:50, 23 February 2010 (UTC) 156:05:17, 23 February 2010 (UTC) 124:05:08, 23 February 2010 (UTC) 33: 1724:{\displaystyle B\subseteq A} 1445:{\displaystyle x\mapsto 1+x} 1413:{\displaystyle x\mapsto x+1} 774:Let me explain my question: 472:extended Euclidean algorithm 4498:{\displaystyle (p+x)^{2}=S} 4001:How to integrate e^sin(x)? 2352:, "The relation induced by 2176:. For example, the formula 1256:? The larger universe (or 476:elliptic curve cryptography 450:Inversion in a Galois Field 4838: 2965:with "+" rather than "−". 2543:{\displaystyle e^{x}=^{x}} 945:{\displaystyle \ln(x^{2})} 614:. Computing an inverse in 4653:is what is denoted there 4071:can be used for this. -- 2460:One way of seeing it is: 1821:one-to-one correspondence 1185:is in B, and that every 4726:{\displaystyle (20p+x)x} 2365:{\displaystyle \varphi } 2345:{\displaystyle \varphi } 1698:{\displaystyle f:D\to A} 1666:{\displaystyle f:D\to B} 4688:{\displaystyle (2p+x)x} 4646:{\displaystyle S-p^{2}} 4085:Very cool. Thank you. 3910:exact for all d<1? 1815:is another name for an 873:express the fact that: 842:express the fact that: 108:98765321 / 1233456789 4788: 4727: 4689: 4647: 4614: 4557: 4499: 4392: 4303: 4253: 4221: 4171: 3975: 3901: 3653: 3457:whatth...corrected! -- 3419:7. Prove that log(x)=∫ 3350: 2956: 2832: 2766: 2692: 2623: 2544: 2366: 2346: 2326: 2233: 1823:is another name for a 1805: 1785: 1765: 1745: 1725: 1699: 1667: 1519: 1499: 1446: 1414: 1382: 1109: 1030: 946: 736: 701: 666: 592: 522: 335: 302: 260: 87:current reference desk 4789: 4728: 4690: 4648: 4615: 4558: 4500: 4393: 4304: 4233: 4222: 4151: 4016:This function has no 3976: 3902: 3633: 3351: 2957: 2833: 2767: 2693: 2624: 2545: 2367: 2347: 2327: 2234: 2129:, avoiding the terms 1806: 1786: 1766: 1746: 1726: 1700: 1668: 1520: 1500: 1447: 1415: 1383: 1296:is not an element of 1288:is not an element of 1110: 1031: 947: 737: 702: 667: 593: 523: 336: 282: 240: 104:98765321 / 1233456789 4741: 4699: 4661: 4624: 4567: 4509: 4464: 4456:and wanting to find 4350: 4230: 4117: 3936: 3607: 2983: 2894: 2777: 2703: 2634: 2555: 2466: 2432:Exponential function 2356: 2336: 2251: 2180: 1795: 1775: 1755: 1735: 1709: 1677: 1645: 1568:The image of F is C. 1509: 1456: 1424: 1392: 1356: 1040: 1036:is injective, while 960: 917: 838:, then how should I 711: 676: 626: 567: 497: 478:and other reasons. 200: 3932:It's exact for all 3423:dt/t for all x: --> 2143:domain of discourse 2066:so that -1 inv_abs 1813:one-to-one function 1258:domain of discourse 889:belonging to A, if 869:, then how sould I 820:is unnecessarily a 804:On the other hand, 4784: 4723: 4685: 4643: 4610: 4553: 4495: 4388: 4387: 4299: 4217: 3971: 3897: 3405:6. Prove that exp: 3391:4. Prove that if x 3346: 3344: 3305: 3237: 3174: 3099: 3028: 2952: 2918: 2828: 2798: 2762: 2724: 2688: 2655: 2619: 2576: 2540: 2500: 2380:is bijective from 2362: 2342: 2322: 2229: 1825:bijective function 1817:injective function 1801: 1781: 1761: 1741: 1721: 1695: 1663: 1515: 1495: 1442: 1410: 1378: 1105: 1026: 942: 732: 697: 662: 588: 518: 400:The Moscow Puzzles 331: 218: 4436:comment added by 4297: 4206: 3916:comment added by 3889: 3852: 3820: 3788: 3764: 3628: 3484:comment added by 3469: 3455: 3395:→x then also (1+x 3326: 3290: 3263: 3222: 3195: 3159: 3125: 3084: 3049: 3013: 2939: 2903: 2816: 2783: 2747: 2709: 2673: 2640: 2597: 2561: 2518: 2485: 2444:comment added by 2239:. Given a domain 2149:as a synonym for 1804:{\displaystyle B} 1784:{\displaystyle f} 1764:{\displaystyle B} 1744:{\displaystyle f} 1594: 1590: 1518:{\displaystyle f} 1280:corresponding to 1218:- only, and that 1193:- only, and that 1119:is bijective. -- 868: 837: 323: 235: 203: 114:comment added by 93: 92: 73: 72: 4829: 4793: 4791: 4790: 4785: 4783: 4782: 4732: 4730: 4729: 4724: 4694: 4692: 4691: 4686: 4652: 4650: 4649: 4644: 4642: 4641: 4619: 4617: 4616: 4611: 4609: 4608: 4563:or equivalently 4562: 4560: 4559: 4554: 4546: 4545: 4521: 4520: 4504: 4502: 4501: 4496: 4488: 4487: 4448: 4397: 4395: 4394: 4389: 4386: 4379: 4378: 4308: 4306: 4305: 4300: 4298: 4296: 4288: 4281: 4280: 4255: 4252: 4247: 4226: 4224: 4223: 4218: 4207: 4205: 4197: 4196: 4195: 4173: 4170: 4165: 4138: 4137: 3980: 3978: 3977: 3972: 3970: 3969: 3951: 3950: 3928: 3906: 3904: 3903: 3898: 3890: 3888: 3887: 3886: 3873: 3872: 3871: 3858: 3853: 3851: 3850: 3849: 3836: 3835: 3826: 3821: 3819: 3818: 3817: 3804: 3803: 3794: 3789: 3787: 3776: 3765: 3763: 3762: 3761: 3743: 3742: 3733: 3732: 3701: 3700: 3699: 3675: 3674: 3655: 3652: 3647: 3629: 3621: 3620: 3611: 3496: 3464: 3456: 3445: 3437: 3381:|x| and use 1). 3355: 3353: 3352: 3347: 3345: 3338: 3337: 3332: 3328: 3327: 3319: 3304: 3278: 3277: 3269: 3265: 3264: 3262: 3251: 3236: 3210: 3209: 3201: 3197: 3196: 3188: 3173: 3147: 3146: 3141: 3137: 3136: 3131: 3127: 3126: 3118: 3098: 3072: 3071: 3066: 3062: 3061: 3060: 3055: 3051: 3050: 3042: 3027: 2999: 2998: 2961: 2959: 2958: 2953: 2951: 2950: 2945: 2941: 2940: 2932: 2917: 2845:COVIZAPIBETEFOKY 2837: 2835: 2834: 2829: 2827: 2826: 2817: 2809: 2797: 2771: 2769: 2768: 2763: 2761: 2760: 2748: 2746: 2735: 2723: 2697: 2695: 2694: 2689: 2687: 2686: 2674: 2666: 2654: 2628: 2626: 2625: 2620: 2618: 2617: 2608: 2607: 2598: 2590: 2575: 2549: 2547: 2546: 2541: 2539: 2538: 2529: 2528: 2519: 2511: 2499: 2478: 2477: 2456: 2371: 2369: 2368: 2363: 2351: 2349: 2348: 2343: 2331: 2329: 2328: 2323: 2276: 2238: 2236: 2235: 2230: 2219: 2211: 1810: 1808: 1807: 1802: 1790: 1788: 1787: 1782: 1770: 1768: 1767: 1762: 1750: 1748: 1747: 1742: 1730: 1728: 1727: 1722: 1704: 1702: 1701: 1696: 1672: 1670: 1669: 1664: 1592: 1588: 1524: 1522: 1521: 1516: 1504: 1502: 1501: 1496: 1451: 1449: 1448: 1443: 1419: 1417: 1416: 1411: 1387: 1385: 1384: 1379: 1377: 1369: 1114: 1112: 1111: 1106: 1101: 1100: 1073: 1053: 1035: 1033: 1032: 1027: 1022: 1021: 994: 951: 949: 948: 943: 938: 937: 866: 835: 741: 739: 738: 733: 731: 723: 718: 706: 704: 703: 698: 696: 688: 683: 671: 669: 668: 663: 649: 641: 636: 597: 595: 594: 589: 587: 579: 574: 527: 525: 524: 519: 517: 509: 504: 340: 338: 337: 332: 324: 322: 321: 320: 301: 296: 280: 279: 278: 259: 254: 238: 236: 234: 220: 217: 150: 147: 144: 141: 138: 135: 126: 75: 38:Mathematics desk 34: 4837: 4836: 4832: 4831: 4830: 4828: 4827: 4826: 4774: 4739: 4738: 4697: 4696: 4695:corresponds to 4659: 4658: 4633: 4622: 4621: 4600: 4565: 4564: 4537: 4512: 4507: 4506: 4479: 4462: 4461: 4431: 4423: 4370: 4348: 4347: 4289: 4272: 4256: 4228: 4227: 4198: 4187: 4174: 4123: 4115: 4114: 4069:Risch algorithm 3999: 3961: 3942: 3934: 3933: 3911: 3878: 3874: 3863: 3859: 3841: 3837: 3827: 3809: 3805: 3795: 3780: 3744: 3734: 3724: 3702: 3691: 3666: 3656: 3612: 3605: 3604: 3479: 3476: 3462: 3435: 3422: 3415: 3398: 3394: 3343: 3342: 3311: 3307: 3306: 3283: 3280: 3279: 3255: 3243: 3239: 3238: 3215: 3212: 3211: 3180: 3176: 3175: 3152: 3149: 3148: 3110: 3106: 3105: 3101: 3100: 3077: 3074: 3073: 3034: 3030: 3029: 3012: 3008: 3007: 3000: 2990: 2981: 2980: 2924: 2920: 2919: 2892: 2891: 2887:Note that it's 2818: 2775: 2774: 2749: 2739: 2701: 2700: 2675: 2632: 2631: 2609: 2599: 2553: 2552: 2530: 2520: 2469: 2464: 2463: 2439: 2434: 2354: 2353: 2334: 2333: 2249: 2248: 2178: 2177: 1793: 1792: 1773: 1772: 1753: 1752: 1733: 1732: 1707: 1706: 1675: 1674: 1643: 1642: 1507: 1506: 1454: 1453: 1422: 1421: 1390: 1389: 1354: 1353: 1254:Binary relation 1181:only, and that 1092: 1038: 1037: 1013: 958: 957: 929: 915: 914: 795:Ln(a^2)=Ln(b^2) 762: 709: 708: 674: 673: 624: 623: 565: 564: 495: 494: 452: 398:Problem 323 in 306: 281: 264: 239: 224: 198: 197: 195: 191: 187: 183: 179: 175: 171: 167: 148: 145: 142: 139: 136: 133: 109: 106: 101: 30: 29: 28: 12: 11: 5: 4835: 4833: 4825: 4824: 4809: 4799:Meni Rosenfeld 4795: 4781: 4777: 4773: 4770: 4767: 4764: 4761: 4758: 4755: 4752: 4749: 4746: 4722: 4719: 4716: 4713: 4710: 4707: 4704: 4684: 4681: 4678: 4675: 4672: 4669: 4666: 4640: 4636: 4632: 4629: 4607: 4603: 4599: 4596: 4593: 4590: 4587: 4584: 4581: 4578: 4575: 4572: 4552: 4549: 4544: 4540: 4536: 4533: 4530: 4527: 4524: 4519: 4515: 4494: 4491: 4486: 4482: 4478: 4475: 4472: 4469: 4422: 4419: 4418: 4417: 4416: 4415: 4385: 4382: 4377: 4373: 4369: 4366: 4363: 4360: 4357: 4327: 4326: 4295: 4292: 4287: 4284: 4279: 4275: 4271: 4268: 4265: 4262: 4259: 4251: 4246: 4243: 4240: 4236: 4216: 4213: 4210: 4204: 4201: 4194: 4190: 4186: 4183: 4180: 4177: 4169: 4164: 4161: 4158: 4154: 4150: 4147: 4144: 4141: 4136: 4133: 4130: 4126: 4122: 4104: 4103: 4102: 4101: 4100: 4099: 4098: 4097: 4073:Meni Rosenfeld 4067:I believe the 4050: 4022:Meni Rosenfeld 3998: 3995: 3994: 3993: 3983:Meni Rosenfeld 3968: 3964: 3960: 3957: 3954: 3949: 3945: 3941: 3908: 3907: 3896: 3893: 3885: 3881: 3877: 3870: 3866: 3862: 3856: 3848: 3844: 3840: 3834: 3830: 3824: 3816: 3812: 3808: 3802: 3798: 3792: 3786: 3783: 3779: 3774: 3771: 3768: 3760: 3757: 3754: 3751: 3747: 3741: 3737: 3731: 3727: 3723: 3720: 3717: 3714: 3711: 3708: 3705: 3698: 3694: 3690: 3687: 3684: 3681: 3678: 3673: 3669: 3665: 3662: 3659: 3651: 3646: 3643: 3640: 3636: 3632: 3627: 3624: 3619: 3615: 3601: 3600: 3596: 3595: 3572: 3571: 3555: 3554: 3544:Meni Rosenfeld 3521: 3520: 3475: 3472: 3471: 3470: 3448:Meni Rosenfeld 3420: 3413: 3396: 3392: 3372: 3357: 3356: 3341: 3336: 3331: 3325: 3322: 3317: 3314: 3310: 3303: 3300: 3297: 3293: 3289: 3286: 3284: 3282: 3281: 3276: 3273: 3268: 3261: 3258: 3254: 3249: 3246: 3242: 3235: 3232: 3229: 3225: 3221: 3218: 3216: 3214: 3213: 3208: 3205: 3200: 3194: 3191: 3186: 3183: 3179: 3172: 3169: 3166: 3162: 3158: 3155: 3153: 3151: 3150: 3145: 3140: 3135: 3130: 3124: 3121: 3116: 3113: 3109: 3104: 3097: 3094: 3091: 3087: 3083: 3080: 3078: 3076: 3075: 3070: 3065: 3059: 3054: 3048: 3045: 3040: 3037: 3033: 3026: 3023: 3020: 3016: 3011: 3006: 3003: 3001: 2997: 2993: 2989: 2988: 2970: 2969: 2963: 2962: 2949: 2944: 2938: 2935: 2930: 2927: 2923: 2916: 2913: 2910: 2906: 2902: 2899: 2885: 2884: 2881: 2880: 2873:Leonhard Euler 2870: 2856: 2855: 2840: 2839: 2838: 2825: 2821: 2815: 2812: 2807: 2804: 2801: 2796: 2793: 2790: 2786: 2782: 2772: 2759: 2756: 2752: 2745: 2742: 2738: 2733: 2730: 2727: 2722: 2719: 2716: 2712: 2708: 2698: 2685: 2682: 2678: 2672: 2669: 2664: 2661: 2658: 2653: 2650: 2647: 2643: 2639: 2629: 2616: 2612: 2606: 2602: 2596: 2593: 2588: 2585: 2582: 2579: 2574: 2571: 2568: 2564: 2560: 2550: 2537: 2533: 2527: 2523: 2517: 2514: 2509: 2506: 2503: 2498: 2495: 2492: 2488: 2484: 2481: 2476: 2472: 2433: 2430: 2429: 2428: 2427: 2426: 2416:Money is tight 2411: 2407: 2403: 2390:Meni Rosenfeld 2361: 2341: 2321: 2318: 2315: 2312: 2309: 2306: 2303: 2300: 2297: 2294: 2291: 2288: 2285: 2282: 2279: 2275: 2271: 2268: 2265: 2262: 2259: 2256: 2228: 2225: 2222: 2218: 2214: 2210: 2206: 2203: 2200: 2197: 2194: 2191: 2188: 2185: 2131:correspondence 2099: 2098: 2097: 2096: 2095: 2094: 2093: 2092: 2091: 2090: 2089: 2088: 2087: 2086: 2085: 2084: 2083: 2082: 2027: 2026: 2025: 2024: 2023: 2022: 2021: 2020: 2019: 2018: 2017: 2016: 2015: 2014: 2013: 2012: 2011: 2010: 1985: 1984: 1983: 1982: 1981: 1980: 1979: 1978: 1977: 1976: 1975: 1974: 1973: 1972: 1971: 1970: 1957: 1953: 1930: 1929: 1928: 1927: 1926: 1925: 1924: 1923: 1922: 1921: 1920: 1919: 1918: 1917: 1885: 1884: 1883: 1882: 1881: 1880: 1879: 1878: 1877: 1876: 1875: 1874: 1848: 1847: 1846: 1845: 1844: 1843: 1842: 1841: 1840: 1839: 1800: 1780: 1760: 1740: 1720: 1717: 1714: 1694: 1691: 1688: 1685: 1682: 1662: 1659: 1656: 1653: 1650: 1630: 1629: 1628: 1627: 1626: 1625: 1624: 1623: 1603: 1602: 1601: 1600: 1599: 1598: 1597: 1596: 1578: 1577: 1576: 1575: 1574: 1573: 1572: 1571: 1570: 1569: 1566: 1552: 1542: 1541: 1540: 1539: 1538: 1537: 1514: 1494: 1491: 1488: 1485: 1482: 1479: 1476: 1473: 1470: 1467: 1464: 1461: 1441: 1438: 1435: 1432: 1429: 1409: 1406: 1403: 1400: 1397: 1376: 1372: 1368: 1364: 1361: 1345: 1344: 1343: 1342: 1341: 1340: 1317: 1316: 1315: 1314: 1313: 1312: 1252:Have you read 1245: 1244: 1243: 1242: 1226: 1225: 1224: 1223: 1201: 1200: 1199: 1198: 1159: 1158: 1157: 1156: 1150: 1149: 1148: 1147: 1141: 1140: 1139: 1138: 1132: 1131: 1121:Meni Rosenfeld 1104: 1099: 1095: 1091: 1088: 1085: 1082: 1079: 1076: 1072: 1068: 1065: 1062: 1059: 1056: 1052: 1048: 1045: 1025: 1020: 1016: 1012: 1009: 1006: 1003: 1000: 997: 993: 989: 986: 983: 980: 977: 974: 971: 968: 965: 941: 936: 932: 928: 925: 922: 761: 758: 757: 756: 730: 726: 722: 717: 695: 691: 687: 682: 661: 658: 655: 652: 648: 644: 640: 635: 631: 586: 582: 578: 573: 516: 512: 508: 503: 491: 490: 451: 448: 433: 432: 430: 423: 422: 408: 407: 406: 381: 380: 379: 378: 377: 376: 356: 355: 354: 353: 330: 327: 319: 316: 313: 309: 305: 300: 295: 292: 289: 285: 277: 274: 271: 267: 263: 258: 253: 250: 247: 243: 233: 230: 227: 223: 216: 213: 210: 206: 193: 189: 185: 181: 177: 173: 169: 165: 159: 158: 105: 102: 100: 97: 95: 91: 90: 82: 81: 71: 70: 64: 48: 41: 40: 31: 15: 14: 13: 10: 9: 6: 4: 3: 2: 4834: 4823: 4819: 4815: 4810: 4808: 4804: 4800: 4796: 4779: 4775: 4771: 4768: 4765: 4762: 4756: 4753: 4750: 4747: 4736: 4720: 4714: 4711: 4708: 4705: 4682: 4676: 4673: 4670: 4667: 4656: 4638: 4634: 4630: 4627: 4605: 4601: 4597: 4594: 4591: 4588: 4582: 4579: 4576: 4573: 4550: 4547: 4542: 4538: 4534: 4531: 4528: 4525: 4522: 4517: 4513: 4492: 4489: 4484: 4476: 4473: 4470: 4459: 4455: 4451: 4450: 4449: 4447: 4443: 4439: 4438:71.70.143.134 4435: 4428: 4420: 4413: 4409: 4405: 4401: 4383: 4380: 4375: 4367: 4364: 4361: 4355: 4345: 4344: 4343: 4342: 4341: 4340: 4336: 4332: 4331:Michael Hardy 4325: 4324: 4323: 4321: 4317: 4313: 4309: 4293: 4290: 4285: 4282: 4277: 4269: 4266: 4263: 4257: 4244: 4241: 4238: 4234: 4214: 4211: 4208: 4202: 4199: 4192: 4184: 4181: 4178: 4162: 4159: 4156: 4152: 4148: 4145: 4142: 4139: 4134: 4131: 4128: 4124: 4120: 4112: 4111:Taylor series 4109: 4096: 4092: 4088: 4087:58.147.60.130 4084: 4083: 4082: 4078: 4074: 4070: 4066: 4065: 4064: 4060: 4056: 4055:58.147.60.130 4051: 4049: 4045: 4041: 4040:Michael Hardy 4038:or the like. 4037: 4033: 4032: 4031: 4027: 4023: 4019: 4015: 4014: 4013: 4012: 4008: 4004: 3996: 3992: 3988: 3984: 3966: 3962: 3958: 3955: 3952: 3947: 3943: 3939: 3931: 3930: 3929: 3927: 3923: 3919: 3918:173.179.59.66 3915: 3894: 3891: 3883: 3879: 3875: 3868: 3864: 3860: 3854: 3846: 3842: 3838: 3832: 3828: 3822: 3814: 3810: 3806: 3800: 3796: 3790: 3784: 3781: 3777: 3772: 3769: 3766: 3758: 3755: 3752: 3749: 3745: 3739: 3735: 3729: 3725: 3721: 3715: 3712: 3709: 3706: 3696: 3692: 3688: 3682: 3679: 3671: 3663: 3660: 3644: 3641: 3638: 3634: 3630: 3625: 3622: 3617: 3613: 3603: 3602: 3598: 3597: 3594: 3590: 3586: 3582: 3578: 3577: 3576: 3570: 3566: 3562: 3557: 3556: 3553: 3549: 3545: 3541: 3537: 3536: 3535: 3534: 3530: 3526: 3525:Michael Hardy 3519: 3515: 3511: 3507: 3503: 3499: 3498: 3497: 3495: 3491: 3487: 3486:173.179.59.66 3483: 3473: 3468: 3465: 3460: 3453: 3449: 3444: 3443: 3442: 3441: 3438: 3433: 3428: 3425: 3417: 3412: 3408: 3403: 3400: 3389: 3387: 3382: 3378: 3374: 3370: 3369: 3365: 3361: 3360:Michael Hardy 3339: 3334: 3329: 3323: 3320: 3315: 3312: 3308: 3295: 3287: 3285: 3274: 3271: 3266: 3259: 3256: 3252: 3247: 3244: 3240: 3227: 3219: 3217: 3206: 3203: 3198: 3192: 3189: 3184: 3181: 3177: 3164: 3156: 3154: 3143: 3138: 3133: 3128: 3122: 3119: 3114: 3111: 3107: 3102: 3089: 3081: 3079: 3068: 3063: 3057: 3052: 3046: 3043: 3038: 3035: 3031: 3018: 3009: 3004: 3002: 2995: 2991: 2979: 2978: 2977: 2975: 2968: 2967: 2966: 2947: 2942: 2936: 2933: 2928: 2925: 2921: 2908: 2900: 2897: 2890: 2889: 2888: 2883: 2882: 2878: 2874: 2871: 2868: 2864: 2861: 2860: 2859: 2854: 2850: 2846: 2841: 2823: 2813: 2810: 2805: 2802: 2788: 2780: 2773: 2757: 2754: 2743: 2740: 2736: 2731: 2728: 2714: 2706: 2699: 2683: 2680: 2670: 2667: 2662: 2659: 2645: 2637: 2630: 2614: 2604: 2594: 2591: 2586: 2583: 2566: 2558: 2551: 2535: 2525: 2515: 2512: 2507: 2504: 2490: 2479: 2474: 2470: 2462: 2461: 2459: 2458: 2457: 2455: 2451: 2447: 2446:173.179.59.66 2443: 2431: 2425: 2421: 2417: 2412: 2408: 2404: 2401: 2400: 2399: 2395: 2391: 2387: 2383: 2379: 2375: 2359: 2339: 2313: 2310: 2307: 2301: 2298: 2295: 2292: 2289: 2286: 2283: 2280: 2277: 2266: 2263: 2260: 2246: 2243:and codomain 2242: 2223: 2220: 2212: 2201: 2195: 2192: 2189: 2183: 2175: 2171: 2170: 2169: 2168: 2164: 2160: 2159:58.147.60.130 2156: 2152: 2148: 2144: 2140: 2136: 2132: 2128: 2124: 2120: 2116: 2112: 2108: 2104: 2081: 2077: 2073: 2072:58.147.60.130 2069: 2065: 2061: 2057: 2053: 2049: 2045: 2044: 2043: 2042: 2041: 2040: 2039: 2038: 2037: 2036: 2035: 2034: 2033: 2032: 2031: 2030: 2029: 2028: 2008: 2003: 2002: 2001: 2000: 1999: 1998: 1997: 1996: 1995: 1994: 1993: 1992: 1991: 1990: 1989: 1988: 1987: 1986: 1969: 1965: 1961: 1958: 1954: 1951: 1946: 1945: 1944: 1943: 1942: 1941: 1940: 1939: 1938: 1937: 1936: 1935: 1934: 1933: 1932: 1931: 1916: 1912: 1908: 1907:58.147.60.130 1904: 1899: 1898: 1897: 1896: 1895: 1894: 1893: 1892: 1891: 1890: 1889: 1888: 1887: 1886: 1873: 1869: 1865: 1860: 1859: 1858: 1857: 1856: 1855: 1854: 1853: 1852: 1851: 1850: 1849: 1838: 1834: 1830: 1829:58.147.60.130 1826: 1822: 1818: 1814: 1798: 1778: 1758: 1738: 1718: 1715: 1712: 1692: 1686: 1683: 1680: 1660: 1654: 1651: 1648: 1640: 1639: 1638: 1637: 1636: 1635: 1634: 1633: 1632: 1631: 1622: 1618: 1614: 1611: 1610: 1609: 1608: 1607: 1606: 1605: 1604: 1586: 1585: 1584: 1583: 1582: 1581: 1580: 1579: 1567: 1564: 1563: 1561: 1557: 1553: 1550: 1549: 1548: 1547: 1546: 1545: 1544: 1543: 1536: 1532: 1528: 1527:58.147.60.130 1512: 1492: 1489: 1483: 1480: 1477: 1471: 1468: 1465: 1459: 1439: 1436: 1433: 1427: 1407: 1404: 1401: 1395: 1362: 1359: 1351: 1350: 1349: 1348: 1347: 1346: 1339: 1335: 1331: 1330:58.147.60.130 1327: 1323: 1322: 1321: 1320: 1319: 1318: 1311: 1307: 1303: 1302:58.147.60.130 1299: 1295: 1291: 1287: 1283: 1279: 1275: 1271: 1267: 1263: 1259: 1255: 1251: 1250: 1249: 1248: 1247: 1246: 1241: 1237: 1233: 1230: 1229: 1228: 1227: 1221: 1217: 1213: 1209: 1205: 1204: 1203: 1202: 1196: 1192: 1188: 1184: 1180: 1176: 1171: 1167: 1163: 1162: 1161: 1160: 1154: 1153: 1152: 1151: 1145: 1144: 1143: 1142: 1136: 1135: 1134: 1133: 1130: 1126: 1122: 1118: 1097: 1093: 1086: 1083: 1077: 1074: 1060: 1046: 1043: 1018: 1014: 1007: 1004: 998: 995: 978: 975: 972: 966: 963: 955: 934: 930: 923: 920: 913: 912: 911: 910: 906: 902: 898: 896: 892: 888: 884: 880: 876: 872: 864: 859: 857: 853: 849: 845: 841: 833: 828: 825: 823: 819: 815: 811: 807: 802: 800: 796: 792: 788: 784: 780: 777:On one hand, 775: 772: 770: 765: 759: 755: 752: 749: 745: 724: 720: 689: 685: 656: 642: 638: 621: 617: 613: 609: 605: 602:, you define 601: 580: 576: 562: 558: 554: 550: 546: 542: 541: 540: 539: 535: 531: 530:174.29.98.151 510: 506: 489: 485: 481: 480:75.62.109.146 477: 473: 469: 468: 467: 466: 462: 458: 457:174.29.98.151 449: 447: 446: 442: 438: 437:Michael Hardy 431: 428: 427: 426: 421: 417: 413: 409: 404: 403: 401: 397: 396: 395: 394: 390: 386: 385:Michael Hardy 375: 371: 367: 362: 361: 360: 359: 358: 357: 352: 348: 344: 343:58.147.60.130 328: 325: 317: 314: 311: 307: 303: 298: 293: 290: 287: 283: 275: 272: 269: 265: 261: 256: 251: 248: 245: 241: 231: 228: 225: 221: 208: 163: 162: 161: 160: 157: 154: 151: 129: 128: 127: 125: 121: 117: 116:71.143.224.27 113: 103: 98: 96: 88: 84: 83: 80: 77: 76: 68: 61: 57: 53: 47: 42: 39: 35: 27: 23: 19: 4734: 4654: 4505:which means 4457: 4453: 4424: 4328: 4310: 4105: 4000: 3909: 3573: 3522: 3505: 3501: 3477: 3474:Square roots 3429: 3426: 3418: 3410: 3406: 3404: 3401: 3399:/n)→exp(x). 3390: 3385: 3383: 3379: 3375: 3371: 3358: 2971: 2964: 2886: 2876: 2866: 2863:Walter Rudin 2857: 2435: 2410:surjection). 2385: 2381: 2377: 2373: 2244: 2240: 2142: 2138: 2134: 2130: 2126: 2122: 2118: 2114: 2110: 2106: 2102: 2100: 2067: 2063: 2059: 2055: 2051: 2047: 1950:respectively 1949: 1902: 1824: 1820: 1816: 1812: 1297: 1293: 1289: 1285: 1281: 1277: 1273: 1269: 1265: 1261: 1219: 1215: 1211: 1207: 1194: 1190: 1186: 1182: 1178: 1174: 1169: 1165: 1116: 899: 894: 890: 886: 882: 878: 874: 870: 862: 860: 855: 851: 847: 843: 839: 831: 829: 826: 821: 817: 813: 809: 805: 803: 798: 794: 790: 786: 782: 778: 776: 773: 768: 766: 763: 743: 619: 615: 611: 607: 603: 599: 560: 556: 552: 548: 544: 492: 453: 434: 424: 399: 382: 107: 94: 78: 4432:—Preceding 4400:Runge–Kutta 4036:Runge–Kutta 3997:Integration 3912:—Preceding 3561:83.81.42.44 3480:—Preceding 2440:—Preceding 2153:instead of 110:—Preceding 99:February 23 67:February 24 46:February 22 26:Mathematics 4737:for which 4460:such that 4108:convergent 4018:elementary 4003:Chirsgayle 2406:relation). 2139:one-to-one 2123:surjection 1903:one-to-one 598:of degree 4404:Bo Jacoby 4312:Bo Jacoby 3538:See also 2127:bijection 2119:injection 1554:When the 891:f(a)=f(b) 789:numbers, 760:Bijection 50:<< 4814:Staecker 4434:unsigned 3914:unsigned 3482:unsigned 3430:(...) -- 2442:unsigned 2151:codomain 2115:codomain 2107:relation 2103:function 2050:inv_abs 1819:, but a 1560:codomain 1222:is in A? 1197:is in A? 824:number! 822:positive 810:positive 787:positive 783:positive 563:) over 112:unsigned 56:February 24:‎ | 22:Archives 20:‎ | 2174:formula 1960:HOOTmag 1864:HOOTmag 1613:HOOTmag 1232:HOOTmag 901:HOOTmag 871:briefly 863:Ln(X^2) 840:briefly 832:Ln(X^2) 814:Ln(k^2) 806:Ln(X^2) 779:Ln(X^2) 769:Ln(X^2) 767:So, is 742:you'll 551:) with 89:pages. 4657:, and 3386:define 2141:, and 2125:, and 2111:domain 2058:= abs( 1556:domain 1292:or if 954:domain 188:, 4321 3542:. -- 2372:from 2155:image 2147:range 2135:range 1452:, or 1420:, or 893:then 797:then 793:, if 547:= GF( 412:Bkell 192:/1234 180:, 321 69:: --> 63:: --> 62:: --> 44:< 16:< 4818:talk 4803:talk 4442:talk 4408:talk 4335:talk 4316:talk 4091:talk 4077:talk 4059:talk 4044:talk 4026:talk 4007:talk 3987:talk 3959:< 3953:< 3922:talk 3589:talk 3585:Dmcq 3565:talk 3548:talk 3529:talk 3514:talk 3510:Dmcq 3490:talk 3452:talk 3364:talk 2849:talk 2450:talk 2420:talk 2394:talk 2163:talk 2076:talk 2054:iff 1964:talk 1911:talk 1868:talk 1833:talk 1705:and 1617:talk 1531:talk 1334:talk 1306:talk 1272:and 1264:and 1236:talk 1125:talk 905:talk 844:f(X) 748:Emil 744:also 534:talk 484:talk 461:talk 441:talk 416:talk 389:talk 370:talk 366:Dmcq 347:talk 184:/123 172:, 21 120:talk 4362:sin 4264:sin 4179:sin 4129:sin 3876:128 3424:0. 3292:lim 3224:lim 3161:lim 3086:lim 3015:lim 2974:TeX 2905:lim 2875:'s 2865:'s 2785:lim 2711:lim 2642:lim 2563:lim 2487:lim 2384:to 2376:to 1827:.) 1751:is 1469:cos 1388:by 1284:if 895:a=b 887:a,b 799:a=b 791:a,b 528:. 205:lim 176:/12 60:Mar 52:Jan 4820:) 4805:) 4772:− 4766:≤ 4706:20 4631:− 4620:. 4598:− 4444:) 4410:) 4402:. 4365:⁡ 4356:∫ 4337:) 4322:. 4318:) 4267:⁡ 4258:∫ 4250:∞ 4235:∑ 4182:⁡ 4168:∞ 4153:∑ 4149:∫ 4132:⁡ 4121:∫ 4113:. 4093:) 4079:) 4061:) 4046:) 4028:) 4009:) 3989:) 3940:− 3924:) 3895:⋯ 3855:− 3839:16 3791:− 3756:− 3710:− 3661:− 3650:∞ 3635:∑ 3591:) 3567:) 3550:) 3531:) 3516:) 3492:) 3459:pm 3432:pm 3366:) 3302:∞ 3299:→ 3234:∞ 3231:→ 3171:∞ 3168:→ 3096:∞ 3093:→ 3025:∞ 3022:→ 2915:∞ 2912:→ 2851:) 2843:-- 2795:∞ 2792:→ 2721:∞ 2718:→ 2652:∞ 2649:→ 2573:∞ 2570:→ 2497:∞ 2494:→ 2452:) 2422:) 2396:) 2360:φ 2340:φ 2302:φ 2293:∈ 2281:∈ 2184:φ 2165:) 2137:, 2133:, 2121:, 2117:, 2113:, 2109:, 2105:, 2078:) 1966:) 1956:C. 1913:) 1905:.) 1870:) 1835:) 1716:⊆ 1690:→ 1658:→ 1619:) 1533:) 1481:π 1472:⁡ 1463:↦ 1431:↦ 1399:↦ 1371:→ 1336:) 1328:? 1308:) 1238:) 1127:) 1087:⁡ 1084:ln 1081:↦ 1067:→ 1055:∖ 1008:⁡ 1005:ln 1002:↦ 988:→ 982:∞ 924:⁡ 921:ln 907:) 897:? 801:. 751:J. 536:) 486:) 463:) 443:) 418:) 391:) 372:) 349:) 341:. 315:− 284:∑ 273:− 242:∑ 229:− 215:∞ 212:→ 168:/1 122:) 58:| 54:| 4816:( 4801:( 4794:. 4780:2 4776:p 4769:S 4763:x 4760:) 4757:x 4754:+ 4751:p 4748:2 4745:( 4735:x 4721:x 4718:) 4715:x 4712:+ 4709:p 4703:( 4683:x 4680:) 4677:x 4674:+ 4671:p 4668:2 4665:( 4655:c 4639:2 4635:p 4628:S 4606:2 4602:p 4595:S 4592:= 4589:x 4586:) 4583:x 4580:+ 4577:p 4574:2 4571:( 4551:S 4548:= 4543:2 4539:x 4535:+ 4532:x 4529:p 4526:2 4523:+ 4518:2 4514:p 4493:S 4490:= 4485:2 4481:) 4477:x 4474:+ 4471:p 4468:( 4458:x 4454:p 4440:( 4414:. 4406:( 4384:x 4381:d 4376:n 4372:) 4368:x 4359:( 4333:( 4314:( 4294:! 4291:n 4286:x 4283:d 4278:n 4274:) 4270:x 4261:( 4245:0 4242:= 4239:n 4215:= 4212:x 4209:d 4203:! 4200:n 4193:n 4189:) 4185:x 4176:( 4163:0 4160:= 4157:n 4146:= 4143:x 4140:d 4135:x 4125:e 4089:( 4075:( 4057:( 4042:( 4024:( 4005:( 3985:( 3967:2 3963:N 3956:d 3948:2 3944:N 3920:( 3892:+ 3884:7 3880:N 3869:4 3865:d 3861:5 3847:5 3843:N 3833:3 3829:d 3823:+ 3815:3 3811:N 3807:8 3801:2 3797:d 3785:N 3782:2 3778:d 3773:+ 3770:N 3767:= 3759:1 3753:n 3750:2 3746:N 3740:n 3736:4 3730:2 3726:! 3722:n 3719:) 3716:n 3713:2 3707:1 3704:( 3697:n 3693:d 3689:! 3686:) 3683:n 3680:2 3677:( 3672:n 3668:) 3664:1 3658:( 3645:0 3642:= 3639:n 3631:= 3626:d 3623:+ 3618:2 3614:N 3587:( 3563:( 3546:( 3527:( 3512:( 3506:x 3502:x 3488:( 3463:a 3450:( 3436:a 3421:1 3414:+ 3411:R 3409:→ 3407:R 3397:n 3393:n 3362:( 3340:. 3335:m 3330:) 3324:m 3321:x 3316:+ 3313:1 3309:( 3296:m 3288:= 3275:x 3272:n 3267:) 3260:x 3257:n 3253:x 3248:+ 3245:1 3241:( 3228:n 3220:= 3207:x 3204:n 3199:) 3193:n 3190:1 3185:+ 3182:1 3178:( 3165:n 3157:= 3144:x 3139:] 3134:n 3129:) 3123:n 3120:1 3115:+ 3112:1 3108:( 3103:[ 3090:n 3082:= 3069:x 3064:] 3058:n 3053:) 3047:n 3044:1 3039:+ 3036:1 3032:( 3019:n 3010:[ 3005:= 2996:x 2992:e 2948:n 2943:) 2937:n 2934:1 2929:+ 2926:1 2922:( 2909:n 2901:= 2898:e 2879:. 2869:; 2847:( 2824:m 2820:) 2814:m 2811:x 2806:+ 2803:1 2800:( 2789:m 2781:= 2758:x 2755:n 2751:) 2744:x 2741:n 2737:x 2732:+ 2729:1 2726:( 2715:n 2707:= 2684:x 2681:n 2677:) 2671:n 2668:1 2663:+ 2660:1 2657:( 2646:n 2638:= 2615:x 2611:] 2605:n 2601:) 2595:n 2592:1 2587:+ 2584:1 2581:( 2578:[ 2567:n 2559:= 2536:x 2532:] 2526:n 2522:) 2516:n 2513:1 2508:+ 2505:1 2502:( 2491:n 2483:[ 2480:= 2475:x 2471:e 2448:( 2418:( 2392:( 2386:C 2382:A 2378:B 2374:A 2320:} 2317:) 2314:y 2311:, 2308:x 2305:( 2299:, 2296:B 2290:y 2287:, 2284:A 2278:x 2274:| 2270:) 2267:y 2264:, 2261:x 2258:( 2255:{ 2245:B 2241:A 2227:) 2224:x 2221:= 2217:| 2213:y 2209:| 2205:( 2202:= 2199:) 2196:y 2193:, 2190:x 2187:( 2161:( 2074:( 2068:y 2064:y 2060:y 2056:x 2052:y 2048:x 1962:( 1909:( 1866:( 1831:( 1799:B 1779:f 1759:B 1739:f 1719:A 1713:B 1693:A 1687:D 1684:: 1681:f 1661:B 1655:D 1652:: 1649:f 1615:( 1595:. 1529:( 1513:f 1493:1 1490:+ 1487:) 1484:x 1478:2 1475:( 1466:x 1460:x 1440:x 1437:+ 1434:1 1428:x 1408:1 1405:+ 1402:x 1396:x 1375:Z 1367:Z 1363:: 1360:f 1332:( 1304:( 1298:B 1294:b 1290:A 1286:a 1282:b 1278:a 1274:B 1270:A 1266:B 1262:A 1234:( 1220:a 1216:a 1212:b 1208:b 1195:a 1191:a 1187:b 1183:b 1179:b 1175:a 1170:b 1166:a 1123:( 1117:f 1103:) 1098:2 1094:x 1090:( 1078:x 1075:, 1071:R 1064:} 1061:0 1058:{ 1051:R 1047:: 1044:g 1024:) 1019:2 1015:x 1011:( 999:x 996:, 992:R 985:) 979:+ 976:, 973:0 970:( 967:: 964:f 940:) 935:2 931:x 927:( 903:( 883:f 879:A 875:f 856:f 852:k 848:A 818:k 729:Z 725:p 721:/ 716:Z 694:Z 690:p 686:/ 681:Z 660:] 657:x 654:[ 651:) 647:Z 643:p 639:/ 634:Z 630:( 620:f 616:F 612:f 608:d 604:F 600:d 585:Z 581:p 577:/ 572:Z 561:x 559:( 557:f 553:p 549:p 545:F 532:( 515:Z 511:n 507:/ 502:Z 482:( 459:( 439:( 414:( 387:( 368:( 345:( 329:1 326:= 318:n 312:b 308:b 304:n 299:b 294:1 291:= 288:n 276:1 270:n 266:b 262:n 257:b 252:1 249:= 246:n 232:2 226:b 222:1 209:b 194:5 190:5 186:4 182:4 178:3 174:3 170:2 166:2 153:™ 149:w 146:a 143:n 140:i 137:a 134:k 118:(

Index

Knowledge (XXG):Reference desk
Archives
Mathematics
Mathematics desk
February 22
Jan
February
Mar
February 24
current reference desk
unsigned
71.143.224.27
talk
05:08, 23 February 2010 (UTC)
kainaw

05:17, 23 February 2010 (UTC)
58.147.60.130
talk
06:50, 23 February 2010 (UTC)
Dmcq
talk
12:07, 23 February 2010 (UTC)
Michael Hardy
talk
13:26, 23 February 2010 (UTC)
Bkell
talk
22:52, 23 February 2010 (UTC)
Michael Hardy

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