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Mathematical fallacy

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3192: 5241: 3691: 324: 3461: 92:. The latter usually applies to a form of argument that does not comply with the valid inference rules of logic, whereas the problematic mathematical step is typically a correct rule applied with a tacit wrong assumption. Beyond pedagogy, the resolution of a fallacy can lead to deeper insights into a subject (e.g., the introduction of 1339: 3179:
the wrong orientation, so as to produce an absurd conclusion. This wrong orientation is usually suggested implicitly by supplying an imprecise diagram of the situation, where relative positions of points or lines are chosen in a way that is actually impossible under the hypotheses of the argument, but non-obviously so.
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In general, such a fallacy is easy to expose by drawing a precise picture of the situation, in which some relative positions will be different from those in the provided diagram. In order to avoid such fallacies, a correct geometric argument using addition or subtraction of distances or angles should
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arise from using an additive equality involving oriented quantities (such as adding vectors along a given line or adding oriented angles in the plane) to a valid identity, but which fixes only the absolute value of (one of) these quantities. This quantity is then incorporated into the equation with
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in which one of the components, basis case or inductive step, is incorrect. Intuitively, proofs by induction work by arguing that if a statement is true in one case, it is true in the next case, and hence by repeatedly applying this, it can be shown to be true for all cases. The following "proof"
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that is hidden by algebraic notation. There is a certain quality of the mathematical fallacy: as typically presented, it leads not only to an absurd result, but does so in a crafty or clever way. Therefore, these fallacies, for pedagogic reasons, usually take the form of spurious
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of AC, and vice versa (in fact, any diagram drawn with sufficiently accurate instruments will verify the above two facts). Because of this, AB is still AR + RB, but AC is actually AQ − QC; and thus the lengths are not necessarily the same.
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the triangle. In fact, O always lies on the circumcircle of the △ABC (except for isosceles and equilateral triangles where AO and OD coincide). Furthermore, it can be shown that, if AB is longer than AC, then R will lie
319:{\displaystyle {\begin{array}{l}\;\;\;{\dfrac {d}{dx}}{\dfrac {1}{x}}\\={\dfrac {d}{d}}{\dfrac {1}{x^{2}}}\\={\dfrac {d\!\!\!\backslash }{d\!\!\!\backslash }}{\dfrac {1}{x^{2}}}\\=-{\dfrac {1}{x^{2}}}\end{array}}} 2320:
and it is essential to check which of these solutions is relevant to the problem at hand. In the above fallacy, the square root that allowed the second equation to be deduced from the first is valid only when
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in a proof, in that a mistake in a proof leads to an invalid proof while in the best-known examples of mathematical fallacies there is some element of concealment or deception in the presentation of the proof.
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The error here is that the rule of multiplying exponents as when going to the third line does not apply unmodified with complex exponents, even if when putting both sides to the power
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has many variants. The following example uses a disguised division by zero to "prove" that 2 = 1, but can be modified to prove that any number equals any other number.
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Examples exist of mathematically correct results derived by incorrect lines of reasoning. Such an argument, however true the conclusion appears to be, is mathematically
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Bogus proofs, calculations, or derivations constructed to produce a correct result in spite of incorrect logic or operations were termed "howlers" by
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The traditional way of presenting a mathematical fallacy is to give an invalid step of deduction mixed in with valid steps, so that the meaning of
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Another example illustrating the danger of taking the square root of both sides of an equation involves the following fundamental identity
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Since the difference between two values of a constant function vanishes, the same definite integral appears on both sides of the equation.
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and shifting them by 1 or indeed any number is allowed. The error really comes to light when we introduce arbitrary integration limits
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after which the antiderivatives may be cancelled yielding 0 = 1. The problem is that antiderivatives are only defined
5275: 3298: 3091:{\displaystyle {\begin{aligned}e^{2\pi i}&=1\\\left(e^{2\pi i}\right)^{i}&=1^{i}\\e^{-2\pi }&=1\\\end{aligned}}} 3380: − 1 = 0 horses in common, and thus are not necessarily the same colour as each other, so the group of 5160: 4368: 2455: 5196: 5172: 4761: 3112: 1762: 459: 4773: 4517: 3267:
As a corollary, one can show that all triangles are equilateral, by showing that AB = BC and AC = BC in the same way.
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is correct, there is a fallacious, invalid cancellation in the middle step. Another classical example of a howler is
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horses. By our previous assumption, all the horses are of the same colour in this new group, since it is a group of
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The error in each of these examples fundamentally lies in the fact that any equation of the form
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Lewis Carroll in numberland: his fantastical mathematical logical life: an agony in eight fits
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by simply substituting the scalar variables of the characteristic polynomial by the matrix.
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The fallacy is in the second to last line, where the square root of both sides is taken:
1836: 864: 502: 2910: 2887: 2745: 4871: 4856: 4778: 4697: 4623: 4263: 2959: 2933: 2867: 2847: 2795: 2725: 2520: 2499: 27:"Invalid proof" redirects here. For any type of invalid proof besides mathematics, see 2442:{\displaystyle 1={\sqrt {1}}={\sqrt {(-1)(-1)}}={\sqrt {-1}}{\sqrt {-1}}=i\cdot i=-1.} 5259: 4996: 4886: 4618: 4581: 4525: 4393: 4388: 3215: 2962:). If this property is not recognized, then errors such as the following can result: 1362:. For instance, while squaring a number gives a unique value, there are two possible 901:
The fallacy is in line 5: the progression from line 4 to line 5 involves division by
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always prove that quantities are being incorporated with their correct orientation.
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When a number is raised to a complex power, the result is not uniquely defined (see
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are often exhibited, and sometimes collected, as illustrations of a concept called
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are equated. Well-known fallacies also exist in elementary Euclidean geometry and
4192: 4153: 4103: 4070: 4017: 4000: 3941: 3887: 1083:{\displaystyle \int {\frac {1}{x\,\log x}}\,dx=1+\int {\frac {1}{x\,\log x}}\,dx} 5201: 4978: 4915: 1387: 1363: 45: 1654:{\displaystyle 5^{2}-5\times 9+{\frac {81}{4}}=4^{2}-4\times 9+{\frac {81}{4}}} 417:{\displaystyle {\frac {16}{64}}={\frac {16\!\!\!/}{6\!\!\!/4}}={\frac {1}{4}}.} 5111: 5105: 5032: 4944: 2538:
is non-negative (when dealing with real numbers), which is not the case here.
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have the same sign, which is not the case here. In this case, it implies that
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Draw the perpendicular bisector of segment BC, which bisects BC at a point D.
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The error in the proof is the assumption in the diagram that the point O is
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Invalid proofs utilizing powers and roots are often of the following kind:
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Barbeau, Ed (1990). "Fallacies, Flaws and Flimflam #19: Dolt's Theorem".
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The error here lies in the incorrect usage of multiple-valued functions.
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is incorrectly extracted or, more generally, where different values of a
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Fundamentals of Complex Analysis Engineering, Science and Mathematics
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Mathematical fallacies exist in many branches of mathematics. In
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For example, the reason why validity fails may be attributed to a
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Alternatively, imaginary roots are obfuscated in the following:
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can be used to give a false proof that 0 = 1. Letting
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and may have been discovered by him. It was published in 1899.
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Exponentiation § Failure of power and logarithm identities
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Draw line OR perpendicular to AB, line OQ perpendicular to AC.
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Therefore, combining all the horses used, we have a group of
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can lead to mathematical fallacies — if the properties of
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Carroll, Lewis (1899). Collingwood, Stuard Dogson (ed.).
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Heath, Sir Thomas Little; Heiberg, Johan Ludvig (1908).
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If we remove a horse from the group, we have a group of
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Thus, AR = AQ, RB = QC, and AB = AR + RB = AQ + QC = AC.
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only the principal value is chosen. When treated as
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on both sides, correctly reduces to 5 = 5.
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horses are the same colour for any positive integer
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The following is an example of a howler involving 5095: 5083: 4942: 4933: 4842: 4817: 4792: 4716: 4668: 4604: 4579: 4551: 4516: 4466: 4420: 4411: 4349: 4315: 4271: 4262: 3109:, both sides produce the same set of values, being 2489:{\displaystyle {\sqrt {xy}}={\sqrt {x}}{\sqrt {y}}} 3685: 3159: 3090: 2942: 2922: 2899: 2876: 2856: 2836: 2804: 2784: 2757: 2734: 2714: 2670: 2529: 2508: 2488: 2441: 2309: 2277: 2248: 2199: 2164: 2111: 2046: 1963: 1851: 1803: 1745: 1653: 1541: 1471: 1427: 1333: 1082: 879: 844: 809: 764: 718: 633: 562: 517: 416: 318: 4138:The thirteen books of Euclid's Elements, Volume 1 3637: 3636: 3635: 3624: 3623: 3622: 3570: 3569: 3568: 3557: 3556: 3555: 3503: 3502: 3501: 3490: 3489: 3488: 3441: – Marking an argument as obvious or trivial 3160:{\displaystyle \{e^{2\pi n}|n\in \mathbb {Z} \}.} 2950:is equal to the left side of the first equality. 1804:{\displaystyle 5-{\frac {9}{2}}=4-{\frac {9}{2}}} 386: 385: 384: 373: 372: 371: 256: 255: 254: 245: 244: 243: 3974:Saff, E. B.; Snider, Arthur David (2013-07-18). 3458:The same fallacy also applies to the following: 3372:The fallacy in this proof arises in line 3. For 3202:, Chapter II, § 1), purports to show that every 1542:{\displaystyle 5^{2}-5\times 9=4^{2}-4\times 9} 1370:. One value can be chosen by convention as the 473:has various meanings, generally less specific. 4359:Affirmative conclusion from a negative premise 3748: 3746: 3376: = 1, the two groups of horses have 4364:Negative conclusion from affirmative premises 4234: 3396: > 1, but fails to be true when 3210:, meaning that two sides of the triangle are 3198:The fallacy of the isosceles triangle, from ( 2112:{\displaystyle \cos x={\sqrt {1-\sin ^{2}x}}} 8: 3763: 3151: 3116: 469:. Outside the field of mathematics the term 123:, typical examples may involve a step where 4072:Mathematical fallacies, flaws, and flimflam 3221:Given a triangle △ABC, prove that AB = AC: 2496:is generally valid only if at least one of 2333:, the second equation is rendered invalid. 5092: 4939: 4814: 4417: 4268: 4241: 4227: 4219: 3950:. Princeton University Press. p. 12. 3353: + 1 horses are the same colour. 944:are ignored. For instance, a naive use of 161: 160: 159: 56:. There is a distinction between a simple 3669: 3656: 3638: 3625: 3616: 3603: 3589: 3571: 3558: 3549: 3536: 3522: 3504: 3491: 3482: 3469: 3465: 3463: 3342: + 1 horses of the same colour. 3147: 3146: 3135: 3123: 3114: 3062: 3048: 3031: 3015: 2980: 2972: 2970: 2935: 2912: 2889: 2869: 2849: 2823: 2817: 2797: 2772: 2770: 2747: 2727: 2701: 2686: 2651: 2633: 2623: 2587: 2557: 2549: 2522: 2501: 2479: 2472: 2459: 2457: 2408: 2398: 2367: 2357: 2349: 2293: 2264: 2240: 2227: 2221: 2183: 2149: 2138: 2095: 2083: 2069: 2032: 2007: 2001: 1946: 1919: 1911: 1838: 1791: 1772: 1764: 1737: 1722: 1701: 1686: 1672: 1641: 1620: 1603: 1582: 1576: 1521: 1496: 1490: 1446: 1408: 1366:of a positive number. The square root is 1324: 1303: 1297: 1292: 1278: 1257: 1251: 1246: 1226: 1213: 1204: 1198: 1193: 1180: 1175: 1170: 1156: 1143: 1134: 1128: 1123: 1117: 1073: 1060: 1051: 1032: 1019: 1010: 1005: 866: 828: 790: 745: 663: 625: 603: 590: 584: 545: 539: 504: 401: 387: 374: 365: 352: 350: 303: 293: 274: 264: 236: 220: 210: 198: 179: 162: 155: 153: 3418: – Class of mathematical expression 3368:, and so all horses are the same colour. 2765:without a prior choice of branch, while 932:as the mathematical study of change and 3927: 3915: 3752: 3737: 3730: 3451: 3327:Thus we have constructed two groups of 3199: 2047:{\displaystyle \cos ^{2}x=1-\sin ^{2}x} 921:is undefined, the argument is invalid. 3235:Let these two lines meet at a point O. 652:, the right is factored by extracting 4214:Math jokes including an invalid proof 4209:More invalid proofs from AhaJokes.com 3838:(6th ed.). Teubner. p. 51. 7: 4105:Mathematical fallacies and paradoxes 4056:Induction and Analogy in Mathematics 3388:horses are of the same colour, then 3349:horses are all the same colour, any 3331:horses all of the same colour, with 2057:which holds as a consequence of the 1757:Take the square root of both sides: 1358:Many functions do not have a unique 634:{\displaystyle a^{2}-b^{2}=ab-b^{2}} 88:is here slightly different from the 4077:Mathematical Association of America 3978:. Harlow, Essex, England: Pearson. 3889:Mathematical Fun, Games and Puzzles 2715:{\displaystyle (-1)^{\frac {1}{2}}} 1386:Care must be taken when taking the 460:proving the Cayley–Hamilton theorem 3429: – Coincidence in mathematics 648:both sides: the left factors as a 328:Anomalous cancellation in calculus 25: 4199:(including literature references) 3943:An Imaginary Tale: The Story of " 3713:'s original "proof" was that any 3309:horses is all of the same colour. 3187:Fallacy of the isosceles triangle 2792:only denotes the principal value 2325:is positive. In particular, when 2061:. Then, by taking a square root, 719:{\displaystyle (a-b)(a+b)=b(a-b)} 5240: 5239: 3778:"Fallacies, Flaws, and Flimflam" 3717:girls have the same colour eyes. 3412: – Kind of arithmetic error 2837:{\displaystyle 1^{\frac {1}{4}}} 2337:Square roots of negative numbers 2165:{\displaystyle -1={\sqrt {1-0}}} 4005:. T.F. Unwin. pp. 190–191. 3861:The College Mathematics Journal 3785:The College Mathematics Journal 3292:There exist several fallacious 3174:Many mathematical fallacies in 821:Combine like terms on the left 4737:Correlation implies causation 4002:The Lewis Carroll Picture Book 3873:10.1080/07468342.1990.11973308 3836:Lehrbuch der Analysis – Teil 1 3299:all horses are the same colour 3136: 2698: 2688: 2390: 2381: 2378: 2369: 1903:, so the equation should read 1171: 713: 701: 692: 680: 677: 665: 426:Here, although the conclusion 41:Certain type of mistaken proof 1: 3305:Let us say that any group of 2452:The fallacy is that the rule 497:be equal, nonzero quantities 3886:Frohlichstein, Jack (1967). 3214:. This fallacy was known to 2785:{\displaystyle {\sqrt {-1}}} 48:, certain kinds of mistaken 4069:Barbeau, Edward J. (2000). 2249:{\displaystyle x^{2}=a^{2}} 1665:These are perfect squares: 1472:{\displaystyle 25-45=16-36} 1382:Positive and negative roots 337:and is commonly known as a 5292: 5161:I'm entitled to my opinion 4160:Cambridge University Press 3815:Mathematics Stack Exchange 2844:has four different values 1351: 33: 26: 5235: 5144: 5017: 4016:Wilson, Robin J. (2008). 3701:Hypotenuse–leg congruence 3422:List of incomplete proofs 3356:This is clearly true for 5266:Recreational mathematics 5187:Motte-and-bailey fallacy 4287:Affirming the consequent 4155:Fallacies in mathematics 3764:Heath & Heiberg 1908 3427:Mathematical coincidence 563:{\displaystyle a^{2}=ab} 483:division-by-zero fallacy 133:multiple valued function 5207:Two wrongs make a right 4538:Denying the correlative 4144:. The University Press. 3940:Nahin, Paul J. (2010). 2310:{\displaystyle x=\pm a} 2278:{\displaystyle a\neq 0} 1428:{\displaystyle -20=-20} 856:Divide by the non-zero 5276:Mathematical fallacies 5192:Psychologist's fallacy 5129:Argument to moderation 5119:Argument from anecdote 5069:Chronological snobbery 4693:Quoting out of context 4660:Overwhelming exception 4543:Suppressed correlative 4443:Quoting out of context 4318:quantificational logic 4292:Denying the antecedent 3834:Heuser, Harro (1989). 3687: 3410:Anomalous cancellation 3195: 3161: 3092: 2944: 2924: 2901: 2878: 2858: 2838: 2806: 2786: 2759: 2736: 2716: 2672: 2531: 2510: 2490: 2443: 2311: 2279: 2250: 2201: 2166: 2113: 2048: 1965: 1853: 1805: 1747: 1655: 1543: 1473: 1429: 1335: 1084: 909:, which is zero since 881: 846: 811: 766: 720: 635: 564: 519: 418: 343:anomalous cancellation 320: 127:is performed, where a 5155:The Four Great Errors 5135:Argumentum ad populum 5124:Argument from silence 4828:Argumentum ad baculum 4606:Faulty generalization 4297:Argument from fallacy 4102:Bunch, Bryan (1997). 3688: 3439:Proof by intimidation 3279:AB, while Q will lie 3241:Draw lines OB and OC. 3194: 3162: 3107:multivalued functions 3093: 2945: 2925: 2902: 2879: 2859: 2839: 2807: 2787: 2760: 2737: 2717: 2673: 2532: 2511: 2491: 2444: 2312: 2285:, has two solutions: 2280: 2251: 2202: 2167: 2122:Evaluating this when 2114: 2049: 1966: 1854: 1806: 1748: 1656: 1544: 1474: 1430: 1348:Multivalued functions 1336: 1085: 930:Mathematical analysis 882: 847: 812: 810:{\displaystyle b+b=b} 767: 765:{\displaystyle a+b=b} 721: 650:difference of squares 636: 565: 520: 419: 321: 5173:Invincible ignorance 4979:Reductio ad Stalinum 4965:Reductio ad Hitlerum 4921:Wisdom of repugnance 4688:Moving the goalposts 4553:Illicit transference 4478:Begging the question 4399:Undistributed middle 4307:Mathematical fallacy 4282:Affirming a disjunct 4205:with some discussion 3776:Barbeau, Ed (1991). 3462: 3113: 2969: 2934: 2911: 2888: 2868: 2848: 2816: 2796: 2769: 2746: 2726: 2685: 2548: 2521: 2500: 2456: 2348: 2292: 2263: 2220: 2210:which is incorrect. 2200:{\displaystyle -1=1} 2182: 2137: 2068: 2000: 1910: 1837: 1763: 1671: 1575: 1489: 1445: 1407: 1390:of both sides of an 1354:Multivalued function 1116: 1004: 946:integration by parts 865: 845:{\displaystyle 2b=b} 827: 789: 744: 662: 583: 538: 503: 349: 152: 62:mathematical fallacy 54:mathematical fallacy 4906:Parade of horribles 4882:In-group favoritism 4708:Syntactic ambiguity 4351:Syllogistic fallacy 4274:propositional logic 3905:Extract of page 207 3294:proofs by induction 2059:Pythagorean theorem 1852:{\displaystyle 5=4} 1302: 1256: 1203: 1185: 1133: 880:{\displaystyle 2=1} 518:{\displaystyle a=b} 102:five colour theorem 4992:Poisoning the well 4809:Proof by assertion 4784:Texas sharpshooter 4718:Questionable cause 4655:Slothful induction 4614:Anecdotal evidence 4474:Circular reasoning 4369:Exclusive premises 4331:Illicit conversion 4110:Dover Publications 3963:Extract of page 12 3918:, Chapter VI, §I.1 3683: 3681: 3288:Proof by induction 3196: 3157: 3088: 3086: 2940: 2923:{\displaystyle -i} 2920: 2900:{\displaystyle -1} 2897: 2874: 2854: 2834: 2802: 2782: 2758:{\displaystyle -i} 2755: 2732: 2712: 2668: 2527: 2506: 2486: 2439: 2307: 2275: 2246: 2197: 2162: 2109: 2044: 1961: 1849: 1801: 1743: 1651: 1539: 1469: 1425: 1331: 1288: 1242: 1189: 1169: 1119: 1080: 877: 842: 807: 776:Use the fact that 762: 716: 631: 560: 515: 414: 316: 314: 310: 281: 262: 227: 208: 189: 177: 121:elementary algebra 98:Euclidean geometry 5253: 5252: 5231: 5230: 5227: 5226: 5167:Ignoratio elenchi 5079: 5078: 4929: 4928: 4891:Not invented here 4596:Converse accident 4518:Correlative-based 4495:Compound question 4438:False attribution 4433:False equivalence 4407: 4406: 4203:Classic fallacies 4119:978-0-486-29664-7 4086:978-0-88385-529-4 4029:978-0-393-06027-0 3985:978-1-292-02375-5 3957:978-1-4008-3029-9 3930:, Chapter VI, §II 3845:978-3-8351-0131-9 3677: 3664: 3647: 3611: 3597: 3580: 3544: 3530: 3513: 3477: 2954:Complex exponents 2943:{\displaystyle i} 2877:{\displaystyle i} 2857:{\displaystyle 1} 2831: 2805:{\displaystyle i} 2780: 2735:{\displaystyle i} 2709: 2659: 2641: 2595: 2565: 2530:{\displaystyle y} 2509:{\displaystyle x} 2484: 2477: 2467: 2416: 2406: 2393: 2362: 2160: 2107: 1974:which, by adding 1954: 1927: 1799: 1780: 1730: 1694: 1649: 1611: 1322: 1276: 1224: 1154: 1071: 1030: 409: 396: 360: 309: 280: 261: 226: 207: 188: 176: 16:(Redirected from 5283: 5243: 5242: 5214:Special pleading 5093: 4954:Appeal to motive 4940: 4916:Stirring symbols 4896:Island mentality 4834:Wishful thinking 4815: 4531:Perfect solution 4508:No true Scotsman 4503:Complex question 4488:Leading question 4467:Question-begging 4453:No true Scotsman 4418: 4341:Quantifier shift 4336:Proof by example 4269: 4243: 4236: 4229: 4220: 4181: 4145: 4143: 4131: 4098: 4075:. MAA Spectrum. 4060: 4059: 4048: 4042: 4041: 4013: 4007: 4006: 3996: 3990: 3989: 3971: 3965: 3961: 3937: 3931: 3925: 3919: 3913: 3907: 3903: 3883: 3877: 3876: 3856: 3850: 3849: 3831: 3825: 3824: 3822: 3821: 3807: 3801: 3800: 3782: 3773: 3767: 3766:, Chapter II, §I 3761: 3755: 3750: 3741: 3735: 3718: 3708: 3702: 3699: 3693: 3692: 3690: 3689: 3684: 3682: 3678: 3670: 3665: 3657: 3648: 3646: 3642: 3630: 3629: 3617: 3612: 3604: 3598: 3590: 3581: 3579: 3575: 3563: 3562: 3550: 3545: 3537: 3531: 3523: 3514: 3512: 3508: 3496: 3495: 3483: 3478: 3470: 3456: 3416:Division by zero 3166: 3164: 3163: 3158: 3150: 3139: 3134: 3133: 3097: 3095: 3094: 3089: 3087: 3073: 3072: 3053: 3052: 3036: 3035: 3030: 3026: 3025: 2991: 2990: 2949: 2947: 2946: 2941: 2930:, of which only 2929: 2927: 2926: 2921: 2906: 2904: 2903: 2898: 2883: 2881: 2880: 2875: 2863: 2861: 2860: 2855: 2843: 2841: 2840: 2835: 2833: 2832: 2824: 2811: 2809: 2808: 2803: 2791: 2789: 2788: 2783: 2781: 2773: 2764: 2762: 2761: 2756: 2741: 2739: 2738: 2733: 2721: 2719: 2718: 2713: 2711: 2710: 2702: 2677: 2675: 2674: 2669: 2661: 2660: 2652: 2643: 2642: 2634: 2632: 2628: 2627: 2622: 2618: 2597: 2596: 2588: 2586: 2582: 2566: 2558: 2536: 2534: 2533: 2528: 2515: 2513: 2512: 2507: 2495: 2493: 2492: 2487: 2485: 2480: 2478: 2473: 2468: 2460: 2448: 2446: 2445: 2440: 2417: 2409: 2407: 2399: 2394: 2368: 2363: 2358: 2332: 2316: 2314: 2313: 2308: 2284: 2282: 2281: 2276: 2255: 2253: 2252: 2247: 2245: 2244: 2232: 2231: 2206: 2204: 2203: 2198: 2171: 2169: 2168: 2163: 2161: 2150: 2129: 2118: 2116: 2115: 2110: 2108: 2100: 2099: 2084: 2053: 2051: 2050: 2045: 2037: 2036: 2012: 2011: 1989: 1987: 1986: 1983: 1980: 1970: 1968: 1967: 1962: 1960: 1956: 1955: 1947: 1928: 1920: 1858: 1856: 1855: 1850: 1830: 1828: 1827: 1824: 1821: 1810: 1808: 1807: 1802: 1800: 1792: 1781: 1773: 1752: 1750: 1749: 1744: 1742: 1741: 1736: 1732: 1731: 1723: 1706: 1705: 1700: 1696: 1695: 1687: 1660: 1658: 1657: 1652: 1650: 1642: 1625: 1624: 1612: 1604: 1587: 1586: 1568: 1566: 1565: 1562: 1559: 1548: 1546: 1545: 1540: 1526: 1525: 1501: 1500: 1478: 1476: 1475: 1470: 1434: 1432: 1431: 1426: 1340: 1338: 1337: 1332: 1323: 1321: 1304: 1301: 1296: 1277: 1275: 1258: 1255: 1250: 1225: 1223: 1205: 1202: 1197: 1184: 1179: 1174: 1155: 1153: 1135: 1132: 1127: 1089: 1087: 1086: 1081: 1072: 1070: 1052: 1031: 1029: 1011: 997:, we may write: 996: 994: 993: 988: 985: 972: 970: 969: 961: 958: 919:division by zero 886: 884: 883: 878: 851: 849: 848: 843: 816: 814: 813: 808: 771: 769: 768: 763: 725: 723: 722: 717: 656:from both terms 640: 638: 637: 632: 630: 629: 608: 607: 595: 594: 569: 567: 566: 561: 550: 549: 524: 522: 521: 516: 477:Division by zero 457: 455: 454: 451: 448: 441: 439: 438: 435: 432: 423: 421: 420: 415: 410: 402: 397: 395: 391: 379: 378: 366: 361: 353: 325: 323: 322: 317: 315: 311: 308: 307: 295: 282: 279: 278: 266: 263: 260: 249: 238: 228: 225: 224: 212: 209: 200: 190: 181: 178: 175: 164: 125:division by zero 70:division by zero 21: 5291: 5290: 5286: 5285: 5284: 5282: 5281: 5280: 5256: 5255: 5254: 5249: 5223: 5197:Rationalization 5140: 5087: 5075: 5013: 4935:Genetic fallacy 4925: 4838: 4813: 4788: 4712: 4703:Sorites paradox 4683:False precision 4664: 4645:Double counting 4600: 4575: 4547: 4512: 4499:Loaded question 4483:Loaded language 4462: 4403: 4345: 4311: 4258: 4247: 4189: 4184: 4170: 4148: 4141: 4134: 4120: 4101: 4087: 4068: 4064: 4063: 4050: 4049: 4045: 4030: 4015: 4014: 4010: 3998: 3997: 3993: 3986: 3973: 3972: 3968: 3958: 3939: 3938: 3934: 3926: 3922: 3914: 3910: 3900: 3885: 3884: 3880: 3858: 3857: 3853: 3846: 3833: 3832: 3828: 3819: 3817: 3809: 3808: 3804: 3780: 3775: 3774: 3770: 3762: 3758: 3751: 3744: 3736: 3732: 3727: 3722: 3721: 3709: 3705: 3700: 3696: 3680: 3679: 3649: 3631: 3618: 3600: 3599: 3582: 3564: 3551: 3533: 3532: 3515: 3497: 3484: 3460: 3459: 3457: 3453: 3448: 3406: 3290: 3189: 3172: 3119: 3111: 3110: 3085: 3084: 3074: 3058: 3055: 3054: 3044: 3037: 3011: 3007: 3006: 3003: 3002: 2992: 2976: 2967: 2966: 2956: 2932: 2931: 2909: 2908: 2886: 2885: 2866: 2865: 2846: 2845: 2819: 2814: 2813: 2794: 2793: 2767: 2766: 2744: 2743: 2724: 2723: 2722:has two values 2697: 2683: 2682: 2647: 2611: 2607: 2606: 2602: 2601: 2575: 2571: 2570: 2546: 2545: 2519: 2518: 2498: 2497: 2454: 2453: 2346: 2345: 2339: 2330: 2290: 2289: 2261: 2260: 2236: 2223: 2218: 2217: 2180: 2179: 2135: 2134: 2127: 2091: 2066: 2065: 2028: 2003: 1998: 1997: 1984: 1981: 1978: 1977: 1975: 1939: 1935: 1908: 1907: 1835: 1834: 1831:on both sides: 1825: 1822: 1819: 1818: 1816: 1761: 1760: 1715: 1711: 1710: 1679: 1675: 1674: 1669: 1668: 1616: 1578: 1573: 1572: 1569:on both sides: 1563: 1560: 1557: 1556: 1554: 1517: 1492: 1487: 1486: 1443: 1442: 1405: 1404: 1384: 1372:principal value 1356: 1350: 1308: 1262: 1209: 1139: 1114: 1113: 1056: 1015: 1002: 1001: 989: 986: 981: 980: 978: 962: 959: 956: 955: 953: 927: 863: 862: 825: 824: 787: 786: 742: 741: 660: 659: 621: 599: 586: 581: 580: 541: 536: 535: 501: 500: 479: 452: 449: 446: 445: 443: 436: 433: 430: 429: 427: 380: 367: 347: 346: 331: 330: 329: 326: 313: 312: 299: 284: 283: 270: 250: 239: 230: 229: 216: 192: 191: 168: 150: 149: 145: 90:logical fallacy 42: 39: 32: 23: 22: 15: 12: 11: 5: 5289: 5287: 5279: 5278: 5273: 5268: 5258: 5257: 5251: 5250: 5248: 5247: 5236: 5233: 5232: 5229: 5228: 5225: 5224: 5222: 5221: 5216: 5211: 5210: 5209: 5199: 5194: 5189: 5184: 5175: 5170: 5163: 5158: 5151: 5145: 5142: 5141: 5139: 5138: 5131: 5126: 5121: 5116: 5115: 5114: 5101: 5099: 5090: 5081: 5080: 5077: 5076: 5074: 5073: 5072: 5071: 5057: 5052: 5047: 5046: 5045: 5036: 5029: 5027:Accomplishment 5018: 5015: 5014: 5012: 5011: 5006: 4999: 4994: 4989: 4984: 4983: 4982: 4975: 4974: 4973: 4956: 4950: 4948: 4937: 4931: 4930: 4927: 4926: 4924: 4923: 4918: 4913: 4908: 4903: 4898: 4893: 4884: 4879: 4874: 4869: 4864: 4859: 4854: 4848: 4846: 4840: 4839: 4837: 4836: 4831: 4823: 4821: 4812: 4811: 4802: 4796: 4794: 4790: 4789: 4787: 4786: 4781: 4779:Slippery slope 4776: 4771: 4766: 4765: 4764: 4754: 4753: 4752: 4745: 4735: 4734: 4733: 4722: 4720: 4714: 4713: 4711: 4710: 4705: 4700: 4698:Slippery slope 4695: 4690: 4685: 4680: 4674: 4672: 4666: 4665: 4663: 4662: 4657: 4652: 4647: 4642: 4633: 4632: 4631: 4626: 4624:Cherry picking 4616: 4610: 4608: 4602: 4601: 4599: 4598: 4593: 4587: 4585: 4577: 4576: 4574: 4573: 4568: 4563: 4557: 4555: 4549: 4548: 4546: 4545: 4540: 4535: 4534: 4533: 4522: 4520: 4514: 4513: 4511: 4510: 4505: 4492: 4491: 4490: 4480: 4470: 4468: 4464: 4463: 4461: 4460: 4455: 4450: 4445: 4440: 4435: 4430: 4424: 4422: 4415: 4409: 4408: 4405: 4404: 4402: 4401: 4396: 4391: 4386: 4381: 4376: 4371: 4366: 4361: 4355: 4353: 4347: 4346: 4344: 4343: 4338: 4333: 4328: 4322: 4320: 4313: 4312: 4310: 4309: 4304: 4299: 4294: 4289: 4284: 4278: 4276: 4266: 4260: 4259: 4248: 4246: 4245: 4238: 4231: 4223: 4217: 4216: 4211: 4206: 4200: 4193:Invalid proofs 4188: 4187:External links 4185: 4183: 4182: 4168: 4150:Maxwell, E. A. 4146: 4132: 4118: 4099: 4085: 4065: 4062: 4061: 4043: 4028: 4008: 3991: 3984: 3966: 3956: 3932: 3920: 3908: 3898: 3878: 3867:(3): 216–218. 3851: 3844: 3826: 3802: 3768: 3756: 3742: 3729: 3728: 3726: 3723: 3720: 3719: 3703: 3694: 3676: 3673: 3668: 3663: 3660: 3655: 3652: 3650: 3645: 3641: 3634: 3628: 3621: 3615: 3610: 3607: 3602: 3601: 3596: 3593: 3588: 3585: 3583: 3578: 3574: 3567: 3561: 3554: 3548: 3543: 3540: 3535: 3534: 3529: 3526: 3521: 3518: 3516: 3511: 3507: 3500: 3494: 3487: 3481: 3476: 3473: 3468: 3467: 3450: 3449: 3447: 3444: 3443: 3442: 3436: 3430: 3424: 3419: 3413: 3405: 3402: 3370: 3369: 3354: 3343: 3336: 3325: 3310: 3289: 3286: 3260: 3259: 3256: 3249: 3242: 3239: 3236: 3233: 3230: 3188: 3185: 3171: 3168: 3156: 3153: 3149: 3145: 3142: 3138: 3132: 3129: 3126: 3122: 3118: 3099: 3098: 3083: 3080: 3077: 3075: 3071: 3068: 3065: 3061: 3057: 3056: 3051: 3047: 3043: 3040: 3038: 3034: 3029: 3024: 3021: 3018: 3014: 3010: 3005: 3004: 3001: 2998: 2995: 2993: 2989: 2986: 2983: 2979: 2975: 2974: 2955: 2952: 2939: 2919: 2916: 2896: 2893: 2873: 2853: 2830: 2827: 2822: 2812:. Similarly, 2801: 2779: 2776: 2754: 2751: 2731: 2708: 2705: 2700: 2696: 2693: 2690: 2679: 2678: 2667: 2664: 2658: 2655: 2650: 2646: 2640: 2637: 2631: 2626: 2621: 2617: 2614: 2610: 2605: 2600: 2594: 2591: 2585: 2581: 2578: 2574: 2569: 2564: 2561: 2556: 2553: 2526: 2505: 2483: 2476: 2471: 2466: 2463: 2450: 2449: 2438: 2435: 2432: 2429: 2426: 2423: 2420: 2415: 2412: 2405: 2402: 2397: 2392: 2389: 2386: 2383: 2380: 2377: 2374: 2371: 2366: 2361: 2356: 2353: 2338: 2335: 2318: 2317: 2306: 2303: 2300: 2297: 2274: 2271: 2268: 2257: 2256: 2243: 2239: 2235: 2230: 2226: 2208: 2207: 2196: 2193: 2190: 2187: 2173: 2172: 2159: 2156: 2153: 2148: 2145: 2142: 2130:, we get that 2120: 2119: 2106: 2103: 2098: 2094: 2090: 2087: 2082: 2079: 2076: 2073: 2055: 2054: 2043: 2040: 2035: 2031: 2027: 2024: 2021: 2018: 2015: 2010: 2006: 1972: 1971: 1959: 1953: 1950: 1945: 1942: 1938: 1934: 1931: 1926: 1923: 1918: 1915: 1899: = – 1869: 1868: 1861: 1860: 1859: 1848: 1845: 1842: 1813: 1812: 1811: 1798: 1795: 1790: 1787: 1784: 1779: 1776: 1771: 1768: 1755: 1754: 1753: 1740: 1735: 1729: 1726: 1721: 1718: 1714: 1709: 1704: 1699: 1693: 1690: 1685: 1682: 1678: 1663: 1662: 1661: 1648: 1645: 1640: 1637: 1634: 1631: 1628: 1623: 1619: 1615: 1610: 1607: 1602: 1599: 1596: 1593: 1590: 1585: 1581: 1551: 1550: 1549: 1538: 1535: 1532: 1529: 1524: 1520: 1516: 1513: 1510: 1507: 1504: 1499: 1495: 1481: 1480: 1479: 1468: 1465: 1462: 1459: 1456: 1453: 1450: 1439:Write this as 1437: 1436: 1435: 1424: 1421: 1418: 1415: 1412: 1383: 1380: 1352:Main article: 1349: 1346: 1342: 1341: 1330: 1327: 1320: 1317: 1314: 1311: 1307: 1300: 1295: 1291: 1287: 1284: 1281: 1274: 1271: 1268: 1265: 1261: 1254: 1249: 1245: 1241: 1238: 1235: 1232: 1229: 1222: 1219: 1216: 1212: 1208: 1201: 1196: 1192: 1188: 1183: 1178: 1173: 1168: 1165: 1162: 1159: 1152: 1149: 1146: 1142: 1138: 1131: 1126: 1122: 1091: 1090: 1079: 1076: 1069: 1066: 1063: 1059: 1055: 1050: 1047: 1044: 1041: 1038: 1035: 1028: 1025: 1022: 1018: 1014: 1009: 926: 923: 899: 898: 890: 889: 888: 887: 876: 873: 870: 854: 853: 852: 841: 838: 835: 832: 819: 818: 817: 806: 803: 800: 797: 794: 774: 773: 772: 761: 758: 755: 752: 749: 728: 727: 726: 715: 712: 709: 706: 703: 700: 697: 694: 691: 688: 685: 682: 679: 676: 673: 670: 667: 643: 642: 641: 628: 624: 620: 617: 614: 611: 606: 602: 598: 593: 589: 572: 571: 570: 559: 556: 553: 548: 544: 527: 526: 525: 514: 511: 508: 478: 475: 413: 408: 405: 400: 394: 390: 383: 377: 370: 364: 359: 356: 327: 306: 302: 298: 292: 289: 286: 285: 277: 273: 269: 259: 253: 248: 242: 235: 232: 231: 223: 219: 215: 206: 203: 197: 194: 193: 187: 184: 174: 171: 167: 158: 157: 148: 147: 146: 144: 141: 79:contradictions 40: 24: 14: 13: 10: 9: 6: 4: 3: 2: 5288: 5277: 5274: 5272: 5269: 5267: 5264: 5263: 5261: 5246: 5238: 5237: 5234: 5220: 5217: 5215: 5212: 5208: 5205: 5204: 5203: 5200: 5198: 5195: 5193: 5190: 5188: 5185: 5183: 5179: 5176: 5174: 5171: 5169: 5168: 5164: 5162: 5159: 5157: 5156: 5152: 5150: 5147: 5146: 5143: 5137: 5136: 5132: 5130: 5127: 5125: 5122: 5120: 5117: 5113: 5110: 5109: 5108: 5107: 5103: 5102: 5100: 5098: 5094: 5091: 5089: 5082: 5070: 5067: 5066: 5065: 5061: 5058: 5056: 5053: 5051: 5048: 5044: 5040: 5037: 5035: 5034: 5030: 5028: 5025: 5024: 5023: 5020: 5019: 5016: 5010: 5007: 5005: 5004: 5000: 4998: 4995: 4993: 4990: 4988: 4985: 4981: 4980: 4976: 4972: 4969: 4968: 4967: 4966: 4962: 4961: 4960: 4957: 4955: 4952: 4951: 4949: 4947: 4946: 4941: 4938: 4936: 4932: 4922: 4919: 4917: 4914: 4912: 4909: 4907: 4904: 4902: 4899: 4897: 4894: 4892: 4888: 4887:Invented here 4885: 4883: 4880: 4878: 4875: 4873: 4870: 4868: 4865: 4863: 4860: 4858: 4855: 4853: 4850: 4849: 4847: 4845: 4841: 4835: 4832: 4830: 4829: 4825: 4824: 4822: 4820: 4816: 4810: 4806: 4803: 4801: 4798: 4797: 4795: 4791: 4785: 4782: 4780: 4777: 4775: 4772: 4770: 4767: 4763: 4760: 4759: 4758: 4755: 4751: 4750: 4746: 4744: 4743: 4739: 4738: 4736: 4732: 4729: 4728: 4727: 4724: 4723: 4721: 4719: 4715: 4709: 4706: 4704: 4701: 4699: 4696: 4694: 4691: 4689: 4686: 4684: 4681: 4679: 4676: 4675: 4673: 4671: 4667: 4661: 4658: 4656: 4653: 4651: 4650:False analogy 4648: 4646: 4643: 4641: 4637: 4634: 4630: 4627: 4625: 4622: 4621: 4620: 4619:Sampling bias 4617: 4615: 4612: 4611: 4609: 4607: 4603: 4597: 4594: 4592: 4589: 4588: 4586: 4584: 4583: 4582:Secundum quid 4578: 4572: 4569: 4567: 4564: 4562: 4559: 4558: 4556: 4554: 4550: 4544: 4541: 4539: 4536: 4532: 4529: 4528: 4527: 4526:False dilemma 4524: 4523: 4521: 4519: 4515: 4509: 4506: 4504: 4500: 4496: 4493: 4489: 4486: 4485: 4484: 4481: 4479: 4475: 4472: 4471: 4469: 4465: 4459: 4456: 4454: 4451: 4449: 4446: 4444: 4441: 4439: 4436: 4434: 4431: 4429: 4426: 4425: 4423: 4419: 4416: 4414: 4410: 4400: 4397: 4395: 4394:Illicit minor 4392: 4390: 4389:Illicit major 4387: 4385: 4382: 4380: 4377: 4375: 4372: 4370: 4367: 4365: 4362: 4360: 4357: 4356: 4354: 4352: 4348: 4342: 4339: 4337: 4334: 4332: 4329: 4327: 4324: 4323: 4321: 4319: 4314: 4308: 4305: 4303: 4300: 4298: 4295: 4293: 4290: 4288: 4285: 4283: 4280: 4279: 4277: 4275: 4270: 4267: 4265: 4261: 4256: 4252: 4244: 4239: 4237: 4232: 4230: 4225: 4224: 4221: 4215: 4212: 4210: 4207: 4204: 4201: 4198: 4194: 4191: 4190: 4186: 4179: 4175: 4171: 4169:0-521-05700-0 4165: 4161: 4157: 4156: 4151: 4147: 4140: 4139: 4133: 4129: 4125: 4121: 4115: 4111: 4107: 4106: 4100: 4096: 4092: 4088: 4082: 4078: 4074: 4073: 4067: 4066: 4057: 4053: 4052:Pólya, George 4047: 4044: 4039: 4035: 4031: 4025: 4021: 4020: 4012: 4009: 4004: 4003: 3995: 3992: 3987: 3981: 3977: 3970: 3967: 3964: 3959: 3953: 3949: 3948: 3944: 3936: 3933: 3929: 3924: 3921: 3917: 3912: 3909: 3906: 3901: 3899:0-486-20789-7 3895: 3891: 3890: 3882: 3879: 3874: 3870: 3866: 3862: 3855: 3852: 3847: 3841: 3837: 3830: 3827: 3816: 3812: 3806: 3803: 3798: 3794: 3790: 3786: 3779: 3772: 3769: 3765: 3760: 3757: 3754: 3749: 3747: 3743: 3739: 3734: 3731: 3724: 3716: 3712: 3707: 3704: 3698: 3695: 3674: 3671: 3666: 3661: 3658: 3653: 3651: 3643: 3639: 3632: 3626: 3619: 3613: 3608: 3605: 3594: 3591: 3586: 3584: 3576: 3572: 3565: 3559: 3552: 3546: 3541: 3538: 3527: 3524: 3519: 3517: 3509: 3505: 3498: 3492: 3485: 3479: 3474: 3471: 3455: 3452: 3445: 3440: 3437: 3434: 3431: 3428: 3425: 3423: 3420: 3417: 3414: 3411: 3408: 3407: 3403: 3401: 3399: 3395: 3391: 3387: 3383: 3379: 3375: 3367: 3363: 3359: 3355: 3352: 3348: 3344: 3341: 3337: 3334: 3330: 3326: 3323: 3319: 3315: 3311: 3308: 3304: 3303: 3302: 3300: 3295: 3287: 3285: 3282: 3278: 3273: 3268: 3265: 3264: 3257: 3254: 3250: 3247: 3243: 3240: 3237: 3234: 3231: 3228: 3224: 3223: 3222: 3219: 3217: 3216:Lewis Carroll 3213: 3209: 3205: 3201: 3193: 3186: 3184: 3180: 3177: 3169: 3167: 3154: 3143: 3140: 3130: 3127: 3124: 3120: 3108: 3104: 3081: 3078: 3076: 3069: 3066: 3063: 3059: 3049: 3045: 3041: 3039: 3032: 3027: 3022: 3019: 3016: 3012: 3008: 2999: 2996: 2994: 2987: 2984: 2981: 2977: 2965: 2964: 2963: 2961: 2953: 2951: 2937: 2917: 2914: 2894: 2891: 2871: 2851: 2828: 2825: 2820: 2799: 2777: 2774: 2752: 2749: 2729: 2706: 2703: 2694: 2691: 2665: 2662: 2656: 2653: 2648: 2644: 2638: 2635: 2629: 2624: 2619: 2615: 2612: 2608: 2603: 2598: 2592: 2589: 2583: 2579: 2576: 2572: 2567: 2562: 2559: 2554: 2551: 2544: 2543: 2542: 2539: 2537: 2524: 2503: 2481: 2474: 2469: 2464: 2461: 2436: 2433: 2430: 2427: 2424: 2421: 2418: 2413: 2410: 2403: 2400: 2395: 2387: 2384: 2375: 2372: 2364: 2359: 2354: 2351: 2344: 2343: 2342: 2336: 2334: 2328: 2324: 2304: 2301: 2298: 2295: 2288: 2287: 2286: 2272: 2269: 2266: 2241: 2237: 2233: 2228: 2224: 2216: 2215: 2214: 2211: 2194: 2191: 2188: 2185: 2178: 2177: 2176: 2157: 2154: 2151: 2146: 2143: 2140: 2133: 2132: 2131: 2126: =  2125: 2104: 2101: 2096: 2092: 2088: 2085: 2080: 2077: 2074: 2071: 2064: 2063: 2062: 2060: 2041: 2038: 2033: 2029: 2025: 2022: 2019: 2016: 2013: 2008: 2004: 1996: 1995: 1994: 1991: 1957: 1951: 1948: 1943: 1940: 1936: 1932: 1929: 1924: 1921: 1916: 1913: 1906: 1905: 1904: 1902: 1898: 1894: 1890: 1886: 1883: =  1882: 1879:only implies 1878: 1875: =  1874: 1867: 1866: 1862: 1846: 1843: 1840: 1833: 1832: 1814: 1796: 1793: 1788: 1785: 1782: 1777: 1774: 1769: 1766: 1759: 1758: 1756: 1738: 1733: 1727: 1724: 1719: 1716: 1712: 1707: 1702: 1697: 1691: 1688: 1683: 1680: 1676: 1667: 1666: 1664: 1646: 1643: 1638: 1635: 1632: 1629: 1626: 1621: 1617: 1613: 1608: 1605: 1600: 1597: 1594: 1591: 1588: 1583: 1579: 1571: 1570: 1552: 1536: 1533: 1530: 1527: 1522: 1518: 1514: 1511: 1508: 1505: 1502: 1497: 1493: 1485: 1484: 1482: 1466: 1463: 1460: 1457: 1454: 1451: 1448: 1441: 1440: 1438: 1422: 1419: 1416: 1413: 1410: 1403: 1402: 1400: 1399: 1398: 1395: 1393: 1389: 1381: 1379: 1377: 1373: 1369: 1365: 1361: 1355: 1347: 1345: 1328: 1325: 1318: 1315: 1312: 1309: 1305: 1298: 1293: 1289: 1285: 1282: 1279: 1272: 1269: 1266: 1263: 1259: 1252: 1247: 1243: 1239: 1236: 1233: 1230: 1227: 1220: 1217: 1214: 1210: 1206: 1199: 1194: 1190: 1186: 1181: 1176: 1166: 1163: 1160: 1157: 1150: 1147: 1144: 1140: 1136: 1129: 1124: 1120: 1112: 1111: 1110: 1108: 1104: 1100: 1096: 1077: 1074: 1067: 1064: 1061: 1057: 1053: 1048: 1045: 1042: 1039: 1036: 1033: 1026: 1023: 1020: 1016: 1012: 1007: 1000: 999: 998: 992: 984: 977: =  976: 968: 965: 952: =  951: 947: 943: 942:differentials 939: 935: 931: 924: 922: 920: 916: 913: =  912: 908: 905: −  904: 897: 896: 892: 891: 874: 871: 868: 861: 860: 859: 855: 839: 836: 833: 830: 823: 822: 820: 804: 801: 798: 795: 792: 785: 784: 783: 779: 775: 759: 756: 753: 750: 747: 740: 739: 737: 733: 729: 710: 707: 704: 698: 695: 689: 686: 683: 674: 671: 668: 658: 657: 655: 651: 647: 644: 626: 622: 618: 615: 612: 609: 604: 600: 596: 591: 587: 579: 578: 577: 573: 557: 554: 551: 546: 542: 534: 533: 532: 528: 512: 509: 506: 499: 498: 496: 492: 488: 487: 486: 484: 476: 474: 472: 468: 467:Edwin Maxwell 463: 461: 424: 411: 406: 403: 398: 392: 388: 381: 375: 368: 362: 357: 354: 344: 340: 336: 304: 300: 296: 290: 287: 275: 271: 267: 251: 240: 233: 221: 217: 213: 204: 201: 195: 185: 182: 172: 169: 165: 142: 140: 138: 134: 130: 126: 122: 117: 115: 111: 107: 103: 99: 95: 94:Pasch's axiom 91: 87: 82: 80: 76: 71: 66: 63: 59: 55: 51: 47: 37: 30: 19: 5271:Proof theory 5182:Naturalistic 5165: 5153: 5133: 5104: 5088:of relevance 5031: 5009:Whataboutism 5001: 4977: 4971:Godwin's law 4963: 4943: 4826: 4819:Consequences 4800:Law/Legality 4774:Single cause 4747: 4740: 4580: 4448:Loki's Wager 4428:Equivocation 4421:Equivocation 4306: 4197:Cut-the-knot 4154: 4137: 4108:. New York: 4104: 4071: 4055: 4046: 4018: 4011: 4001: 3994: 3975: 3969: 3946: 3942: 3935: 3928:Maxwell 1959 3923: 3916:Maxwell 1959 3911: 3888: 3881: 3864: 3860: 3854: 3835: 3829: 3818:. Retrieved 3814: 3805: 3788: 3784: 3771: 3759: 3753:Maxwell 1959 3738:Maxwell 1959 3733: 3714: 3711:George Pólya 3706: 3697: 3454: 3397: 3393: 3389: 3385: 3381: 3377: 3373: 3371: 3365: 3361: 3357: 3350: 3346: 3345:Thus if any 3339: 3332: 3328: 3321: 3317: 3313: 3306: 3291: 3280: 3276: 3271: 3269: 3266: 3262: 3261: 3225:Draw a line 3220: 3200:Maxwell 1959 3197: 3181: 3173: 3102: 3100: 2957: 2680: 2540: 2517: 2451: 2340: 2326: 2322: 2319: 2258: 2212: 2209: 2174: 2123: 2121: 2056: 1992: 1973: 1900: 1896: 1892: 1888: 1884: 1880: 1876: 1872: 1870: 1863: 1396: 1385: 1364:square roots 1357: 1343: 1106: 1102: 1092: 990: 982: 974: 966: 949: 928: 914: 910: 906: 902: 900: 893: 857: 781: 777: 735: 731: 730:Divide out ( 653: 575: 530: 529:Multiply by 494: 490: 480: 470: 464: 425: 338: 332: 118: 109: 106:graph theory 83: 67: 61: 57: 53: 43: 5202:Red herring 4959:Association 4640:Conjunction 4561:Composition 4458:Reification 4374:Existential 4326:Existential 3740:, p. 9 3297:shows that 1483:Rewrite as 1401:Start from 1388:square root 1368:multivalued 77:of obvious 46:mathematics 5260:Categories 5178:Moralistic 5112:Sealioning 5106:Ad nauseam 5033:Ipse dixit 4945:Ad hominem 4769:Regression 4571:Ecological 4384:Four terms 4302:Masked man 3820:2019-10-24 3725:References 2329:is set to 5219:Straw man 5097:Arguments 5086:fallacies 5060:Tradition 5050:Etymology 5022:Authority 5003:Tu quoque 4987:Bulverism 4757:Gambler's 4726:Animistic 4670:Ambiguity 4636:Base rate 4379:Necessity 4251:fallacies 4038:227016411 3797:0746-8342 3227:bisecting 3212:congruent 3208:isosceles 3144:∈ 3128:π 3070:π 3064:− 3020:π 2985:π 2915:− 2892:− 2775:− 2750:− 2692:− 2613:− 2577:− 2560:− 2434:− 2425:⋅ 2411:− 2401:− 2385:− 2373:− 2321:cos  2302:± 2270:≠ 2186:− 2155:− 2141:− 2102:⁡ 2089:− 2075:⁡ 2039:⁡ 2026:− 2014:⁡ 1944:− 1933:− 1917:− 1789:− 1770:− 1720:− 1684:− 1633:× 1627:− 1595:× 1589:− 1534:× 1528:− 1509:× 1503:− 1464:− 1452:− 1420:− 1411:− 1376:nth roots 1316:⁡ 1290:∫ 1270:⁡ 1244:∫ 1218:⁡ 1191:∫ 1148:⁡ 1121:∫ 1065:⁡ 1049:∫ 1024:⁡ 1008:∫ 938:integrals 708:− 672:− 619:− 597:− 574:Subtract 291:− 258:∖ 247:∖ 110:Pseudaria 36:Null ring 5245:Category 4877:Ridicule 4862:Flattery 4852:Children 4749:Post hoc 4629:McNamara 4591:Accident 4566:Division 4413:Informal 4152:(1959). 4054:(1954). 3404:See also 3204:triangle 3176:geometry 3170:Geometry 1392:equality 1099:constant 925:Analysis 917:. Since 137:calculus 5064:Novelty 5039:Poverty 4901:Loyalty 4867:Novelty 4844:Emotion 4793:Appeals 4762:Inverse 4742:Cum hoc 4731:Furtive 4249:Common 4178:0099907 4128:1461270 4095:1725831 3433:Paradox 3324:horses. 3281:outside 1988:⁠ 1976:⁠ 1829:⁠ 1817:⁠ 1567:⁠ 1555:⁠ 1397:Proof: 1360:inverse 995:⁠ 979:⁠ 971:⁠ 954:⁠ 456:⁠ 444:⁠ 440:⁠ 428:⁠ 335:invalid 143:Howlers 86:fallacy 58:mistake 29:Fallacy 5149:Cliché 5084:Other 5055:Nature 5043:Wealth 4678:Accent 4264:Formal 4176:  4166:  4126:  4116:  4093:  4083:  4036:  4026:  3982:  3954:  3896:  3842:  3795:  3277:within 3272:inside 3263:Q.E.D. 2907:, and 2259:where 1865:Q.E.D. 934:limits 895:Q.E.D. 646:Factor 471:howler 339:howler 114:Euclid 100:, the 75:proofs 60:and a 4911:Spite 4805:Stone 4142:(PDF) 3791:(5). 3781:(PDF) 3446:Notes 1095:up to 50:proof 4997:Tone 4872:Pity 4857:Fear 4255:list 4164:ISBN 4114:ISBN 4081:ISBN 4034:OCLC 4024:ISBN 3980:ISBN 3952:ISBN 3894:ISBN 3840:ISBN 3793:ISSN 2742:and 2516:and 1891:and 1815:Add 1553:Add 1105:and 973:and 940:and 493:and 489:Let 481:The 129:root 4316:In 4272:In 4195:at 3869:doi 3253:RHS 3251:By 3246:AAS 3244:By 3229:∠A. 3206:is 2175:or 2093:sin 2072:cos 2030:sin 2005:cos 1887:if 1313:log 1267:log 1215:log 1145:log 1062:log 1021:log 964:log 108:). 104:of 96:of 44:In 18:1=0 5262:: 5180:/ 5062:/ 5041:/ 4889:/ 4807:/ 4638:/ 4501:/ 4497:/ 4476:/ 4174:MR 4172:. 4162:. 4158:. 4124:MR 4122:. 4112:. 4091:MR 4089:. 4079:. 4032:. 3865:21 3863:. 3813:. 3789:22 3787:. 3783:. 3745:^ 3620:49 3609:98 3606:49 3553:26 3542:65 3539:26 3486:19 3475:95 3472:19 3301:. 2884:, 2864:, 2437:1. 1644:81 1606:81 1558:81 1467:36 1461:16 1455:45 1449:25 1423:20 1414:20 1378:. 1109:. 1097:a 983:dx 975:dv 780:= 738:) 734:− 442:= 437:64 431:16 369:16 358:64 355:16 345:: 139:. 116:. 4257:) 4253:( 4242:e 4235:t 4228:v 4180:. 4130:. 4097:. 4040:. 3988:. 3960:. 3947:" 3945:i 3902:. 3875:. 3871:: 3848:. 3823:. 3799:. 3715:n 3675:2 3672:1 3667:= 3662:8 3659:4 3654:= 3644:8 3640:/ 3633:9 3627:/ 3614:= 3595:5 3592:2 3587:= 3577:5 3573:/ 3566:6 3560:/ 3547:= 3528:5 3525:1 3520:= 3510:5 3506:/ 3499:9 3493:/ 3480:= 3398:N 3394:N 3390:N 3386:N 3382:N 3378:N 3374:N 3366:N 3362:N 3358:N 3351:N 3347:N 3340:N 3333:N 3329:N 3322:N 3318:N 3314:N 3307:N 3155:. 3152:} 3148:Z 3141:n 3137:| 3131:n 3125:2 3121:e 3117:{ 3103:i 3082:1 3079:= 3067:2 3060:e 3050:i 3046:1 3042:= 3033:i 3028:) 3023:i 3017:2 3013:e 3009:( 3000:1 2997:= 2988:i 2982:2 2978:e 2938:i 2918:i 2895:1 2872:i 2852:1 2829:4 2826:1 2821:1 2800:i 2778:1 2753:i 2730:i 2707:2 2704:1 2699:) 2695:1 2689:( 2666:1 2663:= 2657:4 2654:1 2649:1 2645:= 2639:4 2636:1 2630:) 2625:2 2620:) 2616:1 2609:( 2604:( 2599:= 2593:4 2590:2 2584:) 2580:1 2573:( 2568:= 2563:1 2555:= 2552:i 2525:y 2504:x 2482:y 2475:x 2470:= 2465:y 2462:x 2431:= 2428:i 2422:i 2419:= 2414:1 2404:1 2396:= 2391:) 2388:1 2382:( 2379:) 2376:1 2370:( 2365:= 2360:1 2355:= 2352:1 2331:π 2327:x 2323:x 2305:a 2299:= 2296:x 2273:0 2267:a 2242:2 2238:a 2234:= 2229:2 2225:x 2195:1 2192:= 2189:1 2158:0 2152:1 2147:= 2144:1 2128:π 2124:x 2105:x 2097:2 2086:1 2081:= 2078:x 2042:x 2034:2 2023:1 2020:= 2017:x 2009:2 1985:2 1982:/ 1979:9 1958:) 1952:2 1949:9 1941:4 1937:( 1930:= 1925:2 1922:9 1914:5 1901:b 1897:a 1893:b 1889:a 1885:b 1881:a 1877:b 1873:a 1847:4 1844:= 1841:5 1826:2 1823:/ 1820:9 1797:2 1794:9 1786:4 1783:= 1778:2 1775:9 1767:5 1739:2 1734:) 1728:2 1725:9 1717:4 1713:( 1708:= 1703:2 1698:) 1692:2 1689:9 1681:5 1677:( 1647:4 1639:+ 1636:9 1630:4 1622:2 1618:4 1614:= 1609:4 1601:+ 1598:9 1592:5 1584:2 1580:5 1564:4 1561:/ 1537:9 1531:4 1523:2 1519:4 1515:= 1512:9 1506:5 1498:2 1494:5 1458:= 1417:= 1329:x 1326:d 1319:x 1310:x 1306:1 1299:b 1294:a 1286:= 1283:x 1280:d 1273:x 1264:x 1260:1 1253:b 1248:a 1240:+ 1237:0 1234:= 1231:x 1228:d 1221:x 1211:x 1207:1 1200:b 1195:a 1187:+ 1182:b 1177:a 1172:| 1167:1 1164:= 1161:x 1158:d 1151:x 1141:x 1137:1 1130:b 1125:a 1107:b 1103:a 1078:x 1075:d 1068:x 1058:x 1054:1 1046:+ 1043:1 1040:= 1037:x 1034:d 1027:x 1017:x 1013:1 991:x 987:/ 967:x 960:/ 957:1 950:u 915:b 911:a 907:b 903:a 875:1 872:= 869:2 858:b 840:b 837:= 834:b 831:2 805:b 802:= 799:b 796:+ 793:b 782:b 778:a 760:b 757:= 754:b 751:+ 748:a 736:b 732:a 714:) 711:b 705:a 702:( 699:b 696:= 693:) 690:b 687:+ 684:a 681:( 678:) 675:b 669:a 666:( 654:b 627:2 623:b 616:b 613:a 610:= 605:2 601:b 592:2 588:a 576:b 558:b 555:a 552:= 547:2 543:a 531:a 513:b 510:= 507:a 495:b 491:a 453:4 450:/ 447:1 434:/ 412:. 407:4 404:1 399:= 393:4 389:/ 382:6 376:/ 363:= 305:2 301:x 297:1 288:= 276:2 272:x 268:1 252:d 241:d 234:= 222:2 218:x 214:1 205:d 202:d 196:= 186:x 183:1 173:x 170:d 166:d 38:. 31:. 20:)

Index

1=0
Fallacy
Null ring
mathematics
proof
division by zero
proofs
contradictions
fallacy
logical fallacy
Pasch's axiom
Euclidean geometry
five colour theorem
graph theory
Euclid
elementary algebra
division by zero
root
multiple valued function
calculus
invalid
anomalous cancellation
proving the Cayley–Hamilton theorem
Edwin Maxwell
division-by-zero fallacy
Factor
difference of squares
Q.E.D.
division by zero
Mathematical analysis

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