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Talk:Prism (geometry)

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trust nail down the bottom one, and keep all the strings taut. If you displace the top in any direction not parallel to a side, while keeping the strings taut, you have an oblique rectangular prism. Or, if you have trouble seeing that, move the top so that two edges stay in the same vertical plane they previously occupied, then (try to) move it perpendicular to that plane (it won't move a finite distance perpendicularly). In either case, the only right angles are on the top and bottom, and you have what must be called an oblique rectangular prism. The rectangular prisms must be the oblique rectangular prisms and the right rectangular prisms.
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The entry under faces in the table, too, was confusing because something like "p + 2" was expected, corresponding to the 2p and 3p in the vertices and edges entries, but that may just have been the result of the confusion set up by the initial paragraph, so I left it alone. An alternative --- p + 2
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current article (quote):"Take a polygon with n vertices, n edges. Its prism has 2n vertices, 3n edges, and 2 + n faces. Take a polyhedron with v vertices, e edges, and f faces. Its prism has 2v vertices, 2e + v edges, 2f + e faces, and 2 + f cells. Take a polychoron with v vertices, e edges, f faces
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If you slice a cylinder lengthways along its axis you get two shapes that have many of the properties of a prism, but are not prisms by the current definition. The solid has one flat face and one that is curved. It's volume is the area of the end face times it's length and its surface area can be
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I suggest "Take a polygon, polyhedron, or polychoron and sum the number of vertices w/ number edges, and number of faces,and,..,number of polychorons(=1). If one takes the prism of the original object, the corresponding sum is 3 times larger." I don't have a citation for this theorem, but it's easy
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To imagine an oblique rectangular prism, picture two identical rigid rectangles, with eyes at the vertices; tie the eyes together in pairs with 4 equal-length inelastic strings. Hold one horizontal; the other will hang below it, also horizontal; that's your right rectangular prism. Have someone you
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A std. dictionary, in case of the analogous right circular cylinder, does not waste the name "circular cylinder" on it: if you make the proper parallel oblique cuts off the ends of a right elliptical cylinder, you get an oblique circular cylinder; the oblique and right circular cylinders together
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I should have said that this along with the formulas, not formulae, already there would provide nice setting for the Pascal's triangle method of counting vertices edges etc on an n-cube:Just go to the nth row of triangle for 1+2x.(I know this method used to be on Knowledge but I can't find it
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There is no inconsistency. Whoever wrote that paragraph was synthesizing from the comments of two older works, both of which mention that they hold minority opinions. I would not consider those older works to be reliable sources, but I'll rewrite that paragraph to mention the opposing
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found in the same way as a prism. But its not a prism and its not a cylinder. What is to stop this being considered a prism? (Aside from the obvious fact that the current definition exludes it by requiring polygonal faces).
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Moreover, the inclusion in this article of an image of these buildings is misleading and confusing given that only two of them are prisms, and one is not. One of my students was in fact confused by this image.
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sides (faces)?" I took the original intent of "an n-sided prism" to be an attempt to explain the nomenclature so, after clarifying the initial definition, I added the sentence about naming at the end.
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uses "side" to refer to (lateral) faces, while "n-sided polygon" uses "side" to refer to edges. The sense of "side" as "face" got the readers to ask "shouldn't a prism with an n-sided base have
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If i'm wrong, come up with a reliable reference that verifies the other supposed meaning. (If you do, the old article still needs work to clarify the illogical terminology.)
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Perhaps a prism could be "A solid with two congruent parallel faces, and where any cross section parallel to those faces is congruent to them." Thoughts?
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In geometry, an n-sided prism is a polyhedron made of an n-sided polygonal base, a translated copy, and n faces joining corresponding sides.
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This passage, which i have rewrit, must reflect a failure of visual imagination by someone reconstructing what they had learned:
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I hope the usual maintainer of this page can fix these issues. I am not proficient in using wikipedia hypertags. Thanks!
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Where is the inconsistency in Euclid's definition of a prism? How is a triangular-based prism in conflict with it?
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and c cells. Its prism has 2v vertices, 2e + v edges, 2f + e faces, and 2c + f cells, and 2 + c hypercells."
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to prove from the above formulae, and there aren't citations for those formulae either.-Rich Peterson
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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People reading that had found it confusing, largely because of the ambiguous use of "side":
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are among the types of right prism, with a rectangular and square base, respectively.
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It is unmathematical to waste those prism terms on the cuboid and the square cuboid.
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What consists of the base on a prism? Length times width?--
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One also can't count on a casual reader to understand
198:, a collaborative effort to improve the coverage of 112:, a collaborative effort to improve the coverage of 240:This article has not yet received a rating on the 602:Knowledge level-5 vital articles in Mathematics 366:Do prism really have to have polygonal faces? 8: 382:cylinder, half of a right circular cylinder. 19: 535: 163: 58: 607:Start-Class vital articles in Mathematics 488:The claim made in this article that the 378:The shape you are describing is a right 592:Knowledge vital articles in Mathematics 165: 60: 627:Unknown-importance Polyhedra articles 397:with two polygonal bases is called a 7: 516:c-67-175-215-221.hsd1.il.comcast.net 295:I say so for the following reasons: 192:This article is within the scope of 106:This article is within the scope of 417:Why the edit to the lead paragraph? 49:It is of interest to the following 597:Start-Class level-5 vital articles 389:with a polygonal base is called a 14: 617:Mid-priority mathematics articles 303:constitue the circular cylinders. 126:Knowledge:WikiProject Mathematics 612:Start-Class mathematics articles 587:Knowledge level-5 vital articles 185: 167: 129:Template:WikiProject Mathematics 93: 83: 62: 29: 20: 348:now.)Best wishes, Rich Peterson 323:I suggest one more good formula 220:Knowledge:WikiProject Polyhedra 146:This article has been rated as 622:Start-Class Polyhedra articles 455:13:49, 30 September 2010 (UTC) 223:Template:WikiProject Polyhedra 1: 529: 421:The previous text had been: 214:and see a list of open tasks. 120:and see a list of open tasks. 567:20:43, 16 October 2020 (UTC) 550:18:37, 16 October 2020 (UTC) 411:17:50, 10 October 2020 (UTC) 268:05:50, 7 November 2005 (UTC) 524:07:37, 23 August 2013 (UTC) 474:01:31, 1 October 2010 (UTC) 643: 582:Start-Class vital articles 242:project's importance scale 319:19:07, 2005 Apr 15 (UTC) 239: 180: 145: 78: 57: 490:Azrieli Towers are prism 482:Azrieli Towers are prism 385:In the same way that "A 358:23:04, 6 June 2009 (UTC) 343:22:51, 6 June 2009 (UTC) 152:project's priority scale 109:WikiProject Mathematics 530:Euclid's inconsistency 195:WikiProject Polyhedra 36:level-5 vital article 132:mathematics articles 226:Polyhedra articles 101:Mathematics portal 45:content assessment 552: 540:comment added by 514:comment added by 279:rectangular prism 256: 255: 252: 251: 248: 247: 162: 161: 158: 157: 634: 559:Bill Cherowitzo 526: 259:Untitled section 228: 227: 224: 221: 218: 189: 182: 181: 171: 164: 134: 133: 130: 127: 124: 103: 98: 97: 87: 80: 79: 74: 66: 59: 42: 33: 32: 25: 24: 16: 642: 641: 637: 636: 635: 633: 632: 631: 572: 571: 532: 509: 486: 419: 368: 325: 261: 225: 222: 219: 216: 215: 131: 128: 125: 122: 121: 99: 92: 72: 43:on Knowledge's 40: 30: 12: 11: 5: 640: 638: 630: 629: 624: 619: 614: 609: 604: 599: 594: 589: 584: 574: 573: 570: 569: 531: 528: 485: 478: 477: 476: 431: 430: 429: 428: 418: 415: 414: 413: 383: 367: 364: 363: 362: 361: 360: 324: 321: 311: 309: 305: 304: 300: 293: 292: 272: 260: 257: 254: 253: 250: 249: 246: 245: 238: 232: 231: 229: 212:the discussion 190: 178: 177: 172: 160: 159: 156: 155: 144: 138: 137: 135: 118:the discussion 105: 104: 88: 76: 75: 67: 55: 54: 48: 26: 13: 10: 9: 6: 4: 3: 2: 639: 628: 625: 623: 620: 618: 615: 613: 610: 608: 605: 603: 600: 598: 595: 593: 590: 588: 585: 583: 580: 579: 577: 568: 564: 560: 555: 554: 553: 551: 547: 543: 539: 527: 525: 521: 517: 513: 506: 502: 501: 499: 495: 491: 484:is incorrect. 483: 479: 475: 471: 467: 463: 459: 458: 457: 456: 452: 448: 442: 440: 436: 435:n-sided prism 426: 425: 424: 423: 422: 416: 412: 408: 404: 400: 396: 392: 388: 384: 381: 377: 376: 375: 372: 365: 359: 355: 351: 346: 345: 344: 340: 336: 331: 330: 329: 322: 320: 318: 315: 301: 298: 297: 296: 290: 286: 285: 280: 276: 275: 274: 270: 269: 266: 258: 243: 237: 234: 233: 230: 213: 209: 205: 201: 197: 196: 191: 188: 184: 183: 179: 176: 173: 170: 166: 153: 149: 143: 140: 139: 136: 119: 115: 111: 110: 102: 96: 91: 89: 86: 82: 81: 77: 71: 68: 65: 61: 56: 52: 46: 38: 37: 27: 23: 18: 17: 542:92.0.106.148 536:— Preceding 533: 510:— Preceding 507: 503: 497: 489: 487: 481: 461: 443: 438: 434: 432: 420: 380:semicircular 373: 369: 350:75.45.106.99 335:75.45.106.99 326: 306: 294: 289:square prism 288: 282: 278: 271: 262: 206:, and other 193: 148:Mid-priority 147: 107: 73:Mid‑priority 51:WikiProjects 34: 480:Claim that 447:PGoldenberg 123:Mathematics 114:mathematics 70:Mathematics 41:Start-class 576:Categories 462:translated 403:DavidCary 217:Polyhedra 208:polytopes 204:polyhedra 175:Polyhedra 39:is rated 557:views.-- 538:unsigned 512:unsigned 494:cylinder 395:cylinder 265:STANG281 200:polygons 466:Tamfang 391:pyramid 150:on the 498:Ace-af 393:.", a 287:, and 284:cuboid 47:scale. 439:n + 2 399:prism 314:Jerzy 281:, or 28:This 563:talk 546:talk 520:talk 470:talk 451:talk 407:talk 401:. -- 387:cone 354:talk 339:talk 277:The 464:. — 317:(t) 236:??? 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STANG281
05:50, 7 November 2005 (UTC)
cuboid
Jerzy
(t)
75.45.106.99

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