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Talk:Truncated icosidodecahedron

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918:(5) A logical explanation (hinted at in the above link) is that the square faces came as the result of distortion into a "rhombic" shape (i.e., their square shape, which are quadrilaterals with equal-length sides) after the solid was generated by a geometric operation, such as expansion. For example, the rhombi-truncated cuboctahedron is generated by truncation of the cuboctahedron, but this leaves rectangles instead of square faces. The "rhombi-" prefix clarifies that the truncated shape must be deformed into the Archimedean solid that has square faces instead of rectangles. You can easily find an explanation like this for all solids that have "rhomb" in their names or alternate names. 921:(6) It just seems odd that the coincidence of planes for some faces should justify a name, when there's often no other direct connection to the named-after solid, especially when there are usually many other solids with closer geometrical connections that did not affect the naming of the new solid. For example, there are many solids that have faces that lie in the same plane as dodecahedra (or tetrahedra, or cubes), yet they don't have some form or portion of the word "dodecahedron" (or "tetrahedron," or "cube") in their name. If anyone can confirm the information as written, please do so. Otherwise, I may change the text and cite the link I have provided above. 84: 74: 53: 176: 158: 22: 906:. This page says, "What does rhombi mean in the name of a polyhedron? Answer: The true answer to this is a bit complex. Students should make a connection between the red (medium shaded) squares that arise in the polyhedra with rhombi in the naming. You could make the connection that the etymology of rhombi meant a square." 897:
On several Knowledge pages, regarding the naming of solids, it is claimed—in all instances, without citation—that the prefix "rhombi-" comes from the fact that some or all of the faces of the solid in question lie in the same plane as the faces of another solid (e.g., the rhombic dodecahedron) that
802: 909:(2) The most obvious meaning of "rhomb-" is related to squares or rhombuses (rhombi). All the polyhedra with "rhomb-" prefixes have square faces. (And there's something special about them, which I'll explain later.) 912:(3) An alternate name for the cuboctahedron is "rhombitetratetrahedron," but the cuboctahedron does not have any set of faces that happen to lie in the same plane as another solid with "rhombic" in its name. 673: 605: 247:
Somebody should make a soccer ball shaped like this ^_^ Of course, it would be much more expensive...but would look so much cooler! I wonder if the aerodynamics would be significantly different...?
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happens to have the name "rhombic" in it. I think this can be shown to be specious (even though I've found this claim on one non-Knowledge page, but also unsourced there) for several reasons:
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https://www.slideshare.net/hcr1991/mathematical-analysis-of-great-rhombicosidodecahedron-the-largest-archimedean-solid/
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Please check the calculation, it is quite simple, and if I am right, correct the formula (and remove this talk).
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If we multiply everything by φ, the edge length becomes 2 and the coordinates are the even permutations of
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I'll change them when I happen to visit the pages ... or maybe, who knows, I'll get ambitious. ;) —
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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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I don't care, didn't add the original term, but it is used ALL over, if you want to change it.
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The solid has 30 square, 20 hexagonal and 12 decagonal faces in total, so its area should be
175: 157: 926: 838: 930: 887: 870: 820: 702: 687: 309: 287: 269: 259: 939: 903: 862: 694: 679: 301: 279: 266: 256: 797:{\displaystyle A_{O}=30a^{2}\left(1+{\sqrt {3}}+{\sqrt {5+2{\sqrt {5}}}}\right)} 102: 922: 79: 196: 192: 829:, and comes out to 175.031044596 by my calculator, while a reference book 831:
The Geometrical Foundation of Natural Structure: A Source Book of Design
188: 15: 861:, although it would be better to have SOURCE to reference! 833:, shows a decimal 174.2880, close!?. How hard could it be!? 668:{\displaystyle (\pm \phi ^{2},\pm 3\phi ,\pm 2\phi ^{2})} 600:{\displaystyle (\pm (\phi +2),\pm 2\phi ,\pm (3\phi +1))} 721: 614: 536: 466: 396: 333: 522:{\displaystyle (\pm 1,\pm \phi ^{3},\pm (2\phi +3))} 452:{\displaystyle (\pm 2,\pm \phi ^{2},\pm (3\phi +2))} 187:, a collaborative effort to improve the coverage of 101:, a collaborative effort to improve the coverage of 904:http://www.geom.uiuc.edu/~teach95/kt95/KTL12t.html 796: 667: 599: 521: 451: 381: 229:This article has not yet received a rating on the 826:The formula used now is referenced on Mathworld 8: 382:{\displaystyle (\pm 1,\pm 1,\pm (4\phi +1))} 19: 850:12 {10} - 10/(4*tan(pi/10))*12 = 92.330506 806:It is equal to 174.2920303 in estimation. 152: 47: 780: 769: 759: 742: 726: 720: 656: 625: 613: 535: 486: 465: 416: 395: 332: 847:20 {6} - 6/(4*tan(pi/6))*20 = 51.961524 844:30 {4} - 4/(4*tan(pi/4))*30 = 1*30 = 30 154: 49: 278:I wonder what we both meant by that. — 961:Unknown-importance Polyhedra articles 7: 181:This article is within the scope of 95:This article is within the scope of 893:The meaning and origin of "rhombi-" 38:It is of interest to the following 14: 951:Low-priority mathematics articles 841:, edge length 1 = n/(4*tan(pi/n)) 115:Knowledge:WikiProject Mathematics 946:Start-Class mathematics articles 174: 156: 118:Template:WikiProject Mathematics 82: 72: 51: 20: 209:Knowledge:WikiProject Polyhedra 135:This article has been rated as 956:Start-Class Polyhedra articles 875:I don't think so, look here : 662: 615: 594: 591: 576: 555: 543: 537: 516: 513: 498: 467: 446: 443: 428: 397: 376: 373: 358: 334: 212:Template:WikiProject Polyhedra 1: 931:01:28, 24 February 2017 (UTC) 203:and see a list of open tasks. 109:and see a list of open tasks. 270:18:24, 7 February 2006 (UTC) 260:06:20, 7 February 2006 (UTC) 871:02:21, 1 January 2015 (UTC) 821:00:21, 1 January 2015 (UTC) 977: 703:17:41, 20 April 2018 (UTC) 688:04:58, 20 April 2018 (UTC) 310:17:41, 20 April 2018 (UTC) 288:04:58, 20 April 2018 (UTC) 231:project's importance scale 857:So I'm in agreement with 709:Error in the area formula 228: 169: 134: 67: 46: 888:13:18, 3 July 2017 (UTC) 141:project's priority scale 320:to put that another way 98:WikiProject Mathematics 798: 669: 601: 523: 453: 383: 28:This article is rated 839:Area of regular n-gon 799: 670: 602: 524: 454: 384: 251:Cartesian coordinates 184:WikiProject Polyhedra 719: 612: 534: 464: 394: 331: 121:mathematics articles 794: 693:I'd go with that! 665: 597: 519: 449: 379: 215:Polyhedra articles 90:Mathematics portal 34:content assessment 787: 785: 764: 245: 244: 241: 240: 237: 236: 151: 150: 147: 146: 968: 880:InternetowyGołąb 803: 801: 800: 795: 793: 789: 788: 786: 781: 770: 765: 760: 747: 746: 731: 730: 674: 672: 671: 666: 661: 660: 630: 629: 606: 604: 603: 598: 528: 526: 525: 520: 491: 490: 458: 456: 455: 450: 421: 420: 388: 386: 385: 380: 217: 216: 213: 210: 207: 178: 171: 170: 160: 153: 123: 122: 119: 116: 113: 92: 87: 86: 76: 69: 68: 63: 55: 48: 31: 25: 24: 16: 976: 975: 971: 970: 969: 967: 966: 965: 936: 935: 895: 853:Total 174.29203 752: 748: 738: 722: 717: 716: 711: 652: 621: 610: 609: 532: 531: 482: 462: 461: 412: 392: 391: 329: 328: 322: 253: 214: 211: 208: 205: 204: 120: 117: 114: 111: 110: 88: 81: 61: 32:on Knowledge's 29: 12: 11: 5: 974: 972: 964: 963: 958: 953: 948: 938: 937: 934: 933: 919: 916: 913: 910: 907: 894: 891: 855: 854: 851: 848: 845: 842: 835: 834: 792: 784: 779: 776: 773: 768: 763: 758: 755: 751: 745: 741: 737: 734: 729: 725: 710: 707: 706: 705: 676: 675: 664: 659: 655: 651: 648: 645: 642: 639: 636: 633: 628: 624: 620: 617: 607: 596: 593: 590: 587: 584: 581: 578: 575: 572: 569: 566: 563: 560: 557: 554: 551: 548: 545: 542: 539: 529: 518: 515: 512: 509: 506: 503: 500: 497: 494: 489: 485: 481: 478: 475: 472: 469: 459: 448: 445: 442: 439: 436: 433: 430: 427: 424: 419: 415: 411: 408: 405: 402: 399: 389: 378: 375: 372: 369: 366: 363: 360: 357: 354: 351: 348: 345: 342: 339: 336: 321: 318: 317: 316: 315: 314: 313: 312: 293: 292: 291: 290: 273: 272: 252: 249: 243: 242: 239: 238: 235: 234: 227: 221: 220: 218: 201:the discussion 179: 167: 166: 161: 149: 148: 145: 144: 133: 127: 126: 124: 107:the discussion 94: 93: 77: 65: 64: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 973: 962: 959: 957: 954: 952: 949: 947: 944: 943: 941: 932: 928: 924: 920: 917: 914: 911: 908: 905: 901: 900: 899: 892: 890: 889: 885: 881: 878: 873: 872: 868: 864: 860: 859:31.11.242.188 852: 849: 846: 843: 840: 837: 836: 832: 828: 825: 824: 823: 822: 818: 814: 813:31.11.242.188 810: 807: 804: 790: 782: 777: 774: 771: 766: 761: 756: 753: 749: 743: 739: 735: 732: 727: 723: 714: 708: 704: 700: 696: 692: 691: 690: 689: 685: 681: 657: 653: 649: 646: 643: 640: 637: 634: 631: 626: 622: 618: 608: 588: 585: 582: 579: 573: 570: 567: 564: 561: 558: 552: 549: 546: 540: 530: 510: 507: 504: 501: 495: 492: 487: 483: 479: 476: 473: 470: 460: 440: 437: 434: 431: 425: 422: 417: 413: 409: 406: 403: 400: 390: 370: 367: 364: 361: 355: 352: 349: 346: 343: 340: 337: 327: 326: 325: 319: 311: 307: 303: 299: 298: 297: 296: 295: 294: 289: 285: 281: 277: 276: 275: 274: 271: 268: 264: 263: 262: 261: 258: 250: 248: 232: 226: 223: 222: 219: 202: 198: 194: 190: 186: 185: 180: 177: 173: 172: 168: 165: 162: 159: 155: 142: 138: 132: 129: 128: 125: 108: 104: 100: 99: 91: 85: 80: 78: 75: 71: 70: 66: 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 896: 874: 856: 830: 811: 808: 805: 715: 712: 677: 323: 254: 246: 195:, and other 182: 137:Low-priority 136: 96: 62:Low‑priority 40:WikiProjects 112:Mathematics 103:mathematics 59:Mathematics 30:Start-class 940:Categories 206:Polyhedra 197:polytopes 193:polyhedra 164:Polyhedra 902:(1) See 863:Tom Ruen 695:Tom Ruen 302:Tom Ruen 300:Indeed! 257:Tom Ruen 189:polygons 680:Tamfang 280:Tamfang 267:Tamfang 139:on the 36:scale. 927:talk 923:Holy 884:talk 867:talk 817:talk 699:talk 684:talk 306:talk 284:talk 225:??? 131:Low 942:: 929:) 886:) 869:) 819:) 736:30 701:) 686:) 654:ϕ 647:± 641:ϕ 635:± 623:ϕ 619:± 583:ϕ 574:± 568:ϕ 562:± 547:ϕ 541:± 505:ϕ 496:± 484:ϕ 480:± 471:± 435:ϕ 426:± 414:ϕ 410:± 401:± 365:ϕ 356:± 347:± 338:± 308:) 286:) 191:, 925:( 882:( 865:( 815:( 791:) 783:5 778:2 775:+ 772:5 767:+ 762:3 757:+ 754:1 750:( 744:2 740:a 733:= 728:O 724:A 697:( 682:( 678:— 663:) 658:2 650:2 644:, 638:3 632:, 627:2 616:( 595:) 592:) 589:1 586:+ 580:3 577:( 571:, 565:2 559:, 556:) 553:2 550:+ 544:( 538:( 517:) 514:) 511:3 508:+ 502:2 499:( 493:, 488:3 477:, 474:1 468:( 447:) 444:) 441:2 438:+ 432:3 429:( 423:, 418:2 407:, 404:2 398:( 377:) 374:) 371:1 368:+ 362:4 359:( 353:, 350:1 344:, 341:1 335:( 304:( 282:( 233:. 143:. 42::

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Tom Ruen
06:20, 7 February 2006 (UTC)
Tamfang
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Tamfang
talk
04:58, 20 April 2018 (UTC)

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