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Ceva's theorem

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45: 27: 2601: 974: 1346: 1631: 1492: 451: 249: 2259: 2048: 758: 2465: 1762: 769: 1208: 1097: 2436: 1219: 2353: 1514: 1375: 334: 135: 2145: 1934: 603: 2119: 1923: 1858: 2596:{\displaystyle {\frac {\overline {BD}}{\overline {DC}}}={\frac {\lambda _{C}}{\lambda _{B}}}\quad {\text{and}}\quad {\frac {\overline {CE}}{\overline {EA}}}={\frac {\lambda _{A}}{\lambda _{C}}}.} 2674:)-face. Each of these points divides the face on which it lies into lobes. Given a cycle of pairs of lobes, the product of the ratios of the volumes of the lobes in each pair is 1. 2680:
gives the area of the triangle formed by three cevians in the case that they are not concurrent. Ceva's theorem can be obtained from it by setting the area equal to zero and solving.
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The theorem also has a well-known generalization to spherical and hyperbolic geometry, replacing the lengths in the ratios with their sines and hyperbolic sines, respectively.
969:{\displaystyle {\frac {\overline {BD}}{\overline {DC}}}={\frac {|\triangle BAD|-|\triangle BOD|}{|\triangle CAD|-|\triangle COD|}}={\frac {|\triangle ABO|}{|\triangle CAO|}}.} 1108: 997: 1677: 551:
The first one is very elementary, using only basic properties of triangle areas. However, several cases have to be considered, depending on the position of the point
2364: 1341:{\displaystyle \left|{\frac {\overline {AF}}{\overline {FB}}}\cdot {\frac {\overline {BD}}{\overline {DC}}}\cdot {\frac {\overline {CE}}{\overline {EA}}}\right|=1,} 2282: 2652:
extends the conclusion of Ceva's theorem that the product of certain ratios is 1. Starting from a point in a simplex, a point is defined inductively on each
1626:{\displaystyle {\frac {\overline {BA}}{\overline {AF}}}\cdot {\frac {\overline {FO}}{\overline {OC}}}\cdot {\frac {\overline {CD}}{\overline {DB}}}=-1.} 1487:{\displaystyle {\frac {\overline {AB}}{\overline {BF}}}\cdot {\frac {\overline {FO}}{\overline {OC}}}\cdot {\frac {\overline {CE}}{\overline {EA}}}=-1} 446:{\displaystyle {\frac {\overline {AF}}{\overline {FB}}}\cdot {\frac {\overline {BD}}{\overline {DC}}}\cdot {\frac {\overline {CE}}{\overline {EA}}}=1,} 244:{\displaystyle {\frac {\overline {AF}}{\overline {FB}}}\cdot {\frac {\overline {BD}}{\overline {DC}}}\cdot {\frac {\overline {CE}}{\overline {EA}}}=1.} 297:, in the sense that it may be stated and proved without using the concepts of angles, areas, and lengths (except for the ratio of the lengths of two 2254:{\displaystyle {\overrightarrow {FO}}-\lambda _{C}{\overrightarrow {FC}}=\lambda _{A}{\overrightarrow {FA}}+\lambda _{B}{\overrightarrow {FB}}.} 2043:{\displaystyle {\overrightarrow {XO}}=\lambda _{A}{\overrightarrow {XA}}+\lambda _{B}{\overrightarrow {XB}}+\lambda _{C}{\overrightarrow {XC}},} 753:{\displaystyle {\frac {|\triangle BOD|}{|\triangle COD|}}={\frac {\overline {BD}}{\overline {DC}}}={\frac {|\triangle BAD|}{|\triangle CAD|}}.} 3109: 2687:
in the plane has been known since the early nineteenth century. The theorem has also been generalized to triangles on other surfaces of
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Experimentally finding the centroid of a triangle with different weights at the vertices: a practical application of Ceva's theorem
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To check the magnitude, note that the area of a triangle of a given height is proportional to its base. So
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includes definitions of cevian triangle, cevian nest, anticevian triangle, Ceva conjugate, and cevapoint
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is supposed to not belong to any line passing through two vertices of the triangle. This implies that
1203:{\displaystyle {\frac {\overline {AF}}{\overline {FB}}}={\frac {|\triangle CAO|}{|\triangle BCO|}}.} 1092:{\displaystyle {\frac {\overline {CE}}{\overline {EA}}}={\frac {|\triangle BCO|}{|\triangle ABO|}},} 590:
is inside the triangle (upper diagram), or one is positive and the other two are negative, the case
3189: 3151: 1796: 1757:{\displaystyle {\frac {\overline {AF}}{\overline {FB}}}={\frac {\overline {AF'}}{\overline {F'B}}}} 559: 3162: 126: 2763: 2276:
are not collinear. It follows that the two members of the equation equal the zero vector, and
2431:{\displaystyle {\frac {\overline {AF}}{\overline {FB}}}={\frac {\lambda _{B}}{\lambda _{A}}},} 2834: 2719: 2714: 1355: 20: 2755: 2788: 2729: 2641:
can be assigned to the vertices such that each cevian intersects the opposite facet at its
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Landy, Steven (December 1988). "A Generalization of Ceva's Theorem to Higher Dimensions".
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Geometric relation between line segments from a triangle's vertices and their intersection
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Wernicke, Paul (November 1927). "The Theorems of Ceva and Menelaus and Their Extension".
2853: 2703: 2634: 571: 465: 310: 3091: 2645:. Moreover, the intersection point of the cevians is the center of mass of the simplex. 2348:{\displaystyle \lambda _{A}{\overrightarrow {FA}}+\lambda _{B}{\overrightarrow {FB}}=0.} 2264:
The left-hand side of this equation is a vector that has the same direction as the line
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Several proofs of the theorem have been given. Two proofs are given in the following.
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Ceva's theorem results immediately by taking the product of the three last equations.
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where the left-hand-side fraction is the signed ratio of the lengths of the collinear
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Grünbaum, Branko; Shephard, G. C. (1995). "Ceva, Menelaus and the Area Principle".
2952: 2913: 2878: 1792: 461: 3137: 3121: 2956: 3054:"Al-Mutaman ibn Hűd, 11the century king of Saragossa and brilliant mathematician" 2819: 2656:-face. This point is the foot of a cevian that goes from the vertex opposite the 294: 82: 3013:
Masal'tsev, L. A. (1994). "Incidence theorems in spaces of constant curvature".
566:, but is somehow more natural and not case dependent. Moreover, it works in any 2642: 583: 586:
is positive since either all three of the ratios are positive, the case where
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in that their equations differ only in sign. By re-writing each in terms of
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Associated with the figures are several terms derived from Ceva's name:
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Ceva's theorem, case 2: the three lines are concurrent at a point
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Ceva's theorem, case 1: the three lines are concurrent at a point
2684: 2649: 2615: 2734: 2626:-simplex as a ray from each vertex to a point on the opposite ( 491: 122: 2841:, pages 177–180, Dover Publishing Co., second revised edition. 2268:, and the right-hand side has the same direction as the line 1767:
But at most one point can cut a segment in a given ratio so
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Russell, John Wellesley (1905). "Ch. 1 §7 Ceva's Theorem".
2114:{\displaystyle \lambda _{A}\lambda _{B}\lambda _{C}\neq 0.} 2939:
Samet, Dov (May 2021). "An Extension of Ceva's Theorem to
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Conics Associated with a Cevian Nest, by Clark Kimberling
1918:{\displaystyle \lambda _{A}+\lambda _{B}+\lambda _{C}=1,} 468:. The converse is often included as part of the theorem. 260:
is taken to be positive or negative according to whether
2139:(see figures), the last equation may be rearranged into 594:
is outside the triangle (lower diagram shows one case).
517:); cevian nest, anticevian triangle, Ceva conjugate. ( 1853:{\displaystyle \lambda _{A},\lambda _{B},\lambda _{C}} 2637:). Then the cevians are concurrent if and only if a 2614:
The theorem can be generalized to higher-dimensional
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The theorem follows by dividing these two equations.
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in some fixed orientation of the line. For example,
1667:. Then by the theorem, the equation also holds for 2595: 2430: 2347: 2253: 2113: 2042: 1917: 1852: 1756: 1625: 1486: 1340: 1202: 1091: 968: 752: 445: 243: 3181: 2977: 1774: 3092:Derivations and applications of Ceva's Theorem 3012: 2272:. These lines have different directions since 2648:Another generalization to higher-dimensional 305:). It is therefore true for triangles in any 3110:Glossary of Encyclopedia of Triangle Centers 1354:The theorem can also be proven easily using 2852:Hopkins, George Irving (1902). "Art. 986". 3069: 3051: 1639:The converse follows as a corollary. Let 278:is defined as having positive value when 2903: 2683:The analogue of the theorem for general 1213:Multiplying these three equations gives 43: 25: 2851: 2817: 2786: 577: 3182: 3133: 2938: 2868: 2753: 3101:Trigonometric Form of Ceva's Theorem 2813: 2811: 2809: 479:. But it was proven much earlier by 475:, who published it in his 1678 work 471:The theorem is often attributed to 13: 3045: 2609: 1177: 1153: 1066: 1042: 979:(Replace the minus with a plus if 943: 919: 888: 863: 839: 814: 727: 703: 639: 615: 536:, the two theorems may be seen as 14: 3211: 3079: 2945:The American Mathematical Monthly 2906:The American Mathematical Monthly 2871:The American Mathematical Monthly 2806: 2796:Journal for Geometry and Graphics 3015:Journal of Mathematical Sciences 2839:Challenging Problems in Geometry 1647:so that the equation holds. Let 3006: 2837:and Charles T. Salkind (1996), 2758:Geometry: Our Cultural Heritage 2532: 2526: 528:The theorem is very similar to 293:Ceva's theorem is a theorem of 3127:Wolfram Demonstrations Project 2971: 2932: 2897: 2862: 2844: 2828: 2780: 2747: 2720:Menelaus's theorem - Knowledge 2064:For Ceva's theorem, the point 1190: 1173: 1166: 1149: 1079: 1062: 1055: 1038: 956: 939: 932: 915: 901: 884: 876: 859: 852: 835: 827: 810: 740: 723: 716: 699: 652: 635: 628: 611: 483:, an eleventh-century king of 1: 2957:10.1080/00029890.2021.1896292 2740: 2730:Stewart's theorem - Knowledge 1807:are the unique three numbers 1775:Using barycentric coordinates 103:), to meet opposite sides at 2557: 2544: 2493: 2480: 2392: 2379: 1748: 1730: 1705: 1692: 1608: 1595: 1575: 1562: 1542: 1529: 1469: 1456: 1436: 1423: 1403: 1390: 1318: 1305: 1285: 1272: 1252: 1239: 1136: 1123: 1025: 1012: 797: 784: 686: 673: 428: 415: 395: 382: 362: 349: 229: 216: 196: 183: 163: 150: 107:respectively. (The segments 96:(not on one of the sides of 7: 3168:Encyclopedia of Mathematics 2697: 1791:, that belongs to the same 264:is to the left or right of 254:In other words, the length 10: 3216: 513:is the cevian triangle of 127:signed lengths of segments 18: 3156:Dynamic Geometry Sketches 3052:Hogendijk, J. B. (1995). 2459:The same reasoning shows 1497:and from the transversal 987:are on opposite sides of 543: 525:is pronounced chev'ian.) 481:Yusuf Al-Mu'taman ibn Hűd 3200:Euclidean plane geometry 3195:Theorems about triangles 2855:Inductive Plane Geometry 2622:. Define a cevian of an 320:is also true: If points 290:and negative otherwise. 2787:Benitez, Julio (2007). 2620:barycentric coordinates 1797:barycentric coordinates 1358:. From the transversal 582:First, the sign of the 560:barycentric coordinates 521:is pronounced Chay'va; 3071:10.1006/hmat.1995.1001 2858:. D.C. Heath & Co. 2597: 2432: 2349: 2255: 2115: 2044: 1919: 1854: 1758: 1671:. Comparing the two, 1643:be given on the lines 1627: 1488: 1342: 1204: 1093: 970: 754: 558:The second proof uses 447: 328:respectively so that 245: 59: 41: 2835:Alfred S. Posamentier 2754:Holme, Audun (2010). 2715:Circumcevian triangle 2598: 2433: 2350: 2256: 2116: 2045: 1920: 1855: 1759: 1628: 1489: 1343: 1205: 1094: 971: 755: 448: 246: 47: 29: 21:Ceva (disambiguation) 3058:Historia Mathematica 2980:Mathematics Magazine 2762:. Springer. p.  2725:Triangle - Knowledge 2466: 2365: 2283: 2146: 2072: 1935: 1867: 1811: 1678: 1515: 1376: 1220: 1109: 998: 770: 604: 578:Using triangle areas 335: 136: 19:For other uses, see 3125:by Jay Warendorff, 2704:Projective geometry 1779:Given three points 1659:be the point where 498:are the cevians of 316:A slightly adapted 74:. Given a triangle 70:is a theorem about 3135:Weisstein, Eric W. 3027:10.1007/BF01249519 2824:. Clarendon Press. 2735:Cevian - Knowledge 2689:constant curvature 2593: 2428: 2345: 2251: 2111: 2040: 1915: 1850: 1754: 1623: 1484: 1356:Menelaus's theorem 1338: 1200: 1089: 966: 750: 443: 241: 92:to a common point 88:be drawn from the 64:Euclidean geometry 60: 42: 3086:Menelaus and Ceva 2773:978-3-642-14440-0 2709:Median (geometry) 2639:mass distribution 2588: 2561: 2560: 2547: 2530: 2524: 2497: 2496: 2483: 2423: 2396: 2395: 2382: 2358:It follows that 2337: 2309: 2246: 2218: 2190: 2162: 2127:the intersection 2123:If one takes for 2035: 2007: 1979: 1951: 1752: 1751: 1733: 1709: 1708: 1695: 1612: 1611: 1598: 1579: 1578: 1565: 1546: 1545: 1532: 1473: 1472: 1459: 1440: 1439: 1426: 1407: 1406: 1393: 1322: 1321: 1308: 1289: 1288: 1275: 1256: 1255: 1242: 1195: 1140: 1139: 1126: 1084: 1029: 1028: 1015: 961: 906: 801: 800: 787: 745: 690: 689: 676: 657: 530:Menelaus' theorem 432: 431: 418: 399: 398: 385: 366: 365: 352: 233: 232: 219: 200: 199: 186: 167: 166: 153: 3207: 3176: 3148: 3147: 3138:"Ceva's Theorem" 3075: 3073: 3039: 3038: 3021:(4): 3201–3206. 3010: 3004: 3003: 2975: 2969: 2968: 2936: 2930: 2929: 2901: 2895: 2894: 2866: 2860: 2859: 2848: 2842: 2832: 2826: 2825: 2815: 2804: 2803: 2793: 2784: 2778: 2777: 2761: 2751: 2711:– an application 2673: 2666: 2659: 2655: 2632: 2625: 2602: 2600: 2599: 2594: 2589: 2587: 2586: 2577: 2576: 2567: 2562: 2556: 2548: 2543: 2535: 2534: 2531: 2528: 2525: 2523: 2522: 2513: 2512: 2503: 2498: 2492: 2484: 2479: 2471: 2470: 2455: 2454: 2449: 2448: 2437: 2435: 2434: 2429: 2424: 2422: 2421: 2412: 2411: 2402: 2397: 2391: 2383: 2378: 2370: 2369: 2354: 2352: 2351: 2346: 2338: 2333: 2325: 2323: 2322: 2310: 2305: 2297: 2295: 2294: 2275: 2271: 2267: 2260: 2258: 2257: 2252: 2247: 2242: 2234: 2232: 2231: 2219: 2214: 2206: 2204: 2203: 2191: 2186: 2178: 2176: 2175: 2163: 2158: 2150: 2138: 2134: 2130: 2126: 2120: 2118: 2117: 2112: 2104: 2103: 2094: 2093: 2084: 2083: 2067: 2056: 2053:for every point 2049: 2047: 2046: 2041: 2036: 2031: 2023: 2021: 2020: 2008: 2003: 1995: 1993: 1992: 1980: 1975: 1967: 1965: 1964: 1952: 1947: 1939: 1924: 1922: 1921: 1916: 1905: 1904: 1892: 1891: 1879: 1878: 1859: 1857: 1856: 1851: 1849: 1848: 1836: 1835: 1823: 1822: 1806: 1803:with respect of 1802: 1790: 1782: 1770: 1763: 1761: 1760: 1755: 1753: 1747: 1743: 1734: 1729: 1728: 1716: 1715: 1710: 1704: 1696: 1691: 1683: 1682: 1670: 1666: 1662: 1658: 1654: 1650: 1646: 1642: 1632: 1630: 1629: 1624: 1613: 1607: 1599: 1594: 1586: 1585: 1580: 1574: 1566: 1561: 1553: 1552: 1547: 1541: 1533: 1528: 1520: 1519: 1507: 1500: 1493: 1491: 1490: 1485: 1474: 1468: 1460: 1455: 1447: 1446: 1441: 1435: 1427: 1422: 1414: 1413: 1408: 1402: 1394: 1389: 1381: 1380: 1368: 1361: 1347: 1345: 1344: 1339: 1328: 1324: 1323: 1317: 1309: 1304: 1296: 1295: 1290: 1284: 1276: 1271: 1263: 1262: 1257: 1251: 1243: 1238: 1230: 1229: 1209: 1207: 1206: 1201: 1196: 1194: 1193: 1176: 1170: 1169: 1152: 1146: 1141: 1135: 1127: 1122: 1114: 1113: 1098: 1096: 1095: 1090: 1085: 1083: 1082: 1065: 1059: 1058: 1041: 1035: 1030: 1024: 1016: 1011: 1003: 1002: 990: 986: 982: 975: 973: 972: 967: 962: 960: 959: 942: 936: 935: 918: 912: 907: 905: 904: 887: 879: 862: 856: 855: 838: 830: 813: 807: 802: 796: 788: 783: 775: 774: 759: 757: 756: 751: 746: 744: 743: 726: 720: 719: 702: 696: 691: 685: 677: 672: 664: 663: 658: 656: 655: 638: 632: 631: 614: 608: 593: 589: 554: 538:projective duals 516: 512: 501: 497: 477:De lineis rectis 459: 452: 450: 449: 444: 433: 427: 419: 414: 406: 405: 400: 394: 386: 381: 373: 372: 367: 361: 353: 348: 340: 339: 327: 323: 289: 285: 281: 277: 276: 272: 267: 263: 259: 258: 250: 248: 247: 242: 234: 228: 220: 215: 207: 206: 201: 195: 187: 182: 174: 173: 168: 162: 154: 149: 141: 140: 120: 119: 115: 111: 106: 102: 95: 87: 80: 58: 51: 40: 33: 3215: 3214: 3210: 3209: 3208: 3206: 3205: 3204: 3190:Affine geometry 3180: 3179: 3161: 3082: 3048: 3046:Further reading 3043: 3042: 3011: 3007: 2992:10.2307/2690569 2976: 2972: 2937: 2933: 2918:10.2307/2300222 2902: 2898: 2883:10.2307/2322390 2877:(10): 936–939. 2867: 2863: 2849: 2845: 2833: 2829: 2816: 2807: 2791: 2785: 2781: 2774: 2752: 2748: 2743: 2700: 2678:Routh's theorem 2668: 2661: 2657: 2653: 2627: 2623: 2612: 2610:Generalizations 2582: 2578: 2572: 2568: 2566: 2549: 2536: 2533: 2527: 2518: 2514: 2508: 2504: 2502: 2485: 2472: 2469: 2467: 2464: 2463: 2452: 2451: 2446: 2445: 2417: 2413: 2407: 2403: 2401: 2384: 2371: 2368: 2366: 2363: 2362: 2326: 2324: 2318: 2314: 2298: 2296: 2290: 2286: 2284: 2281: 2280: 2273: 2269: 2265: 2235: 2233: 2227: 2223: 2207: 2205: 2199: 2195: 2179: 2177: 2171: 2167: 2151: 2149: 2147: 2144: 2143: 2136: 2132: 2128: 2124: 2099: 2095: 2089: 2085: 2079: 2075: 2073: 2070: 2069: 2065: 2054: 2024: 2022: 2016: 2012: 1996: 1994: 1988: 1984: 1968: 1966: 1960: 1956: 1940: 1938: 1936: 1933: 1932: 1900: 1896: 1887: 1883: 1874: 1870: 1868: 1865: 1864: 1844: 1840: 1831: 1827: 1818: 1814: 1812: 1809: 1808: 1804: 1800: 1788: 1780: 1777: 1768: 1736: 1735: 1721: 1717: 1714: 1697: 1684: 1681: 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125:.) Then, using 117: 113: 109: 108: 104: 97: 93: 85: 75: 53: 49: 35: 31: 24: 17: 12: 11: 5: 3213: 3203: 3202: 3197: 3192: 3178: 3177: 3163:"Ceva theorem" 3159: 3149: 3130: 3122:Ceva's Theorem 3118: 3113: 3107: 3098: 3089: 3081: 3080:External links 3078: 3077: 3076: 3047: 3044: 3041: 3040: 3005: 2986:(4): 254–268. 2970: 2951:(5): 435–445. 2931: 2912:(9): 468–472. 2896: 2861: 2843: 2827: 2805: 2779: 2772: 2745: 2744: 2742: 2739: 2738: 2737: 2732: 2727: 2722: 2717: 2712: 2706: 2699: 2696: 2643:center of mass 2611: 2608: 2604: 2603: 2592: 2585: 2581: 2575: 2571: 2565: 2559: 2555: 2552: 2546: 2542: 2539: 2521: 2517: 2511: 2507: 2501: 2495: 2491: 2488: 2482: 2478: 2475: 2439: 2438: 2427: 2420: 2416: 2410: 2406: 2400: 2394: 2390: 2387: 2381: 2377: 2374: 2356: 2355: 2344: 2341: 2336: 2332: 2329: 2321: 2317: 2313: 2308: 2304: 2301: 2293: 2289: 2262: 2261: 2250: 2245: 2241: 2238: 2230: 2226: 2222: 2217: 2213: 2210: 2202: 2198: 2194: 2189: 2185: 2182: 2174: 2170: 2166: 2161: 2157: 2154: 2110: 2107: 2102: 2098: 2092: 2088: 2082: 2078: 2051: 2050: 2039: 2034: 2030: 2027: 2019: 2015: 2011: 2006: 2002: 1999: 1991: 1987: 1983: 1978: 1974: 1971: 1963: 1959: 1955: 1950: 1946: 1943: 1926: 1925: 1914: 1911: 1908: 1903: 1899: 1895: 1890: 1886: 1882: 1877: 1873: 1847: 1843: 1839: 1834: 1830: 1826: 1821: 1817: 1787:, and a point 1776: 1773: 1765: 1764: 1750: 1746: 1742: 1739: 1732: 1727: 1724: 1720: 1713: 1707: 1703: 1700: 1694: 1690: 1687: 1634: 1633: 1622: 1619: 1616: 1610: 1606: 1603: 1597: 1593: 1590: 1583: 1577: 1573: 1570: 1564: 1560: 1557: 1550: 1544: 1540: 1537: 1531: 1527: 1524: 1495: 1494: 1483: 1480: 1477: 1471: 1467: 1464: 1458: 1454: 1451: 1444: 1438: 1434: 1431: 1425: 1421: 1418: 1411: 1405: 1401: 1398: 1392: 1388: 1385: 1349: 1348: 1337: 1334: 1331: 1327: 1320: 1316: 1313: 1307: 1303: 1300: 1293: 1287: 1283: 1280: 1274: 1270: 1267: 1260: 1254: 1250: 1247: 1241: 1237: 1234: 1226: 1211: 1210: 1199: 1192: 1188: 1185: 1182: 1179: 1175: 1168: 1164: 1161: 1158: 1155: 1151: 1144: 1138: 1134: 1131: 1125: 1121: 1118: 1100: 1099: 1088: 1081: 1077: 1074: 1071: 1068: 1064: 1057: 1053: 1050: 1047: 1044: 1040: 1033: 1027: 1023: 1020: 1014: 1010: 1007: 991:.) Similarly, 977: 976: 965: 958: 954: 951: 948: 945: 941: 934: 930: 927: 924: 921: 917: 910: 903: 899: 896: 893: 890: 886: 882: 878: 874: 871: 868: 865: 861: 854: 850: 847: 844: 841: 837: 833: 829: 825: 822: 819: 816: 812: 805: 799: 795: 792: 786: 782: 779: 761: 760: 749: 742: 738: 735: 732: 729: 725: 718: 714: 711: 708: 705: 701: 694: 688: 684: 681: 675: 671: 668: 661: 654: 650: 647: 644: 641: 637: 630: 626: 623: 620: 617: 613: 584:left-hand side 579: 576: 545: 542: 506:(the triangle 454: 453: 442: 439: 436: 430: 426: 423: 417: 413: 410: 403: 397: 393: 390: 384: 380: 377: 370: 364: 360: 357: 351: 347: 344: 324:are chosen on 252: 251: 240: 237: 231: 227: 224: 218: 214: 211: 204: 198: 194: 191: 185: 181: 178: 171: 165: 161: 158: 152: 148: 145: 68:Ceva's theorem 15: 9: 6: 4: 3: 2: 3212: 3201: 3198: 3196: 3193: 3191: 3188: 3187: 3185: 3174: 3170: 3169: 3164: 3160: 3157: 3153: 3150: 3145: 3144: 3139: 3136: 3131: 3128: 3124: 3123: 3119: 3117: 3114: 3111: 3108: 3106: 3102: 3099: 3097: 3093: 3090: 3087: 3084: 3083: 3072: 3067: 3063: 3059: 3055: 3050: 3049: 3036: 3032: 3028: 3024: 3020: 3016: 3009: 3001: 2997: 2993: 2989: 2985: 2981: 2974: 2966: 2962: 2958: 2954: 2950: 2946: 2943:-Simplices". 2942: 2935: 2927: 2923: 2919: 2915: 2911: 2907: 2900: 2892: 2888: 2884: 2880: 2876: 2872: 2865: 2857: 2856: 2847: 2840: 2836: 2831: 2823: 2822: 2821:Pure Geometry 2814: 2812: 2810: 2801: 2797: 2790: 2783: 2775: 2769: 2765: 2760: 2759: 2750: 2746: 2736: 2733: 2731: 2728: 2726: 2723: 2721: 2718: 2716: 2713: 2710: 2707: 2705: 2702: 2701: 2695: 2692: 2690: 2686: 2681: 2679: 2675: 2671: 2664: 2660:-face, in a ( 2651: 2646: 2644: 2640: 2636: 2630: 2621: 2617: 2607: 2590: 2583: 2579: 2573: 2569: 2563: 2553: 2550: 2540: 2537: 2519: 2515: 2509: 2505: 2499: 2489: 2486: 2476: 2473: 2462: 2461: 2460: 2457: 2444: 2443:line segments 2425: 2418: 2414: 2408: 2404: 2398: 2388: 2385: 2375: 2372: 2361: 2360: 2359: 2342: 2339: 2334: 2330: 2327: 2319: 2315: 2311: 2306: 2302: 2299: 2291: 2287: 2279: 2278: 2277: 2248: 2243: 2239: 2236: 2228: 2224: 2220: 2215: 2211: 2208: 2200: 2196: 2192: 2187: 2183: 2180: 2172: 2168: 2164: 2159: 2155: 2152: 2142: 2141: 2140: 2131:of the lines 2121: 2108: 2105: 2100: 2096: 2090: 2086: 2080: 2076: 2062: 2060: 2037: 2032: 2028: 2025: 2017: 2013: 2009: 2004: 2000: 1997: 1989: 1985: 1981: 1976: 1972: 1969: 1961: 1957: 1953: 1948: 1944: 1941: 1931: 1930: 1929: 1912: 1909: 1906: 1901: 1897: 1893: 1888: 1884: 1880: 1875: 1871: 1863: 1862: 1861: 1845: 1841: 1837: 1832: 1828: 1824: 1819: 1815: 1798: 1794: 1786: 1783:that are not 1772: 1744: 1740: 1737: 1725: 1722: 1718: 1711: 1701: 1698: 1688: 1685: 1674: 1673: 1672: 1637: 1620: 1617: 1614: 1604: 1601: 1591: 1588: 1581: 1571: 1568: 1558: 1555: 1548: 1538: 1535: 1525: 1522: 1511: 1510: 1509: 1506: 1481: 1478: 1475: 1465: 1462: 1452: 1449: 1442: 1432: 1429: 1419: 1416: 1409: 1399: 1396: 1386: 1383: 1372: 1371: 1370: 1367: 1357: 1352: 1351:as required. 1335: 1332: 1329: 1325: 1314: 1311: 1301: 1298: 1291: 1281: 1278: 1268: 1265: 1258: 1248: 1245: 1235: 1232: 1224: 1216: 1215: 1214: 1197: 1186: 1183: 1180: 1162: 1159: 1156: 1142: 1132: 1129: 1119: 1116: 1105: 1104: 1103: 1086: 1075: 1072: 1069: 1051: 1048: 1045: 1031: 1021: 1018: 1008: 1005: 994: 993: 992: 963: 952: 949: 946: 928: 925: 922: 908: 897: 894: 891: 880: 872: 869: 866: 848: 845: 842: 831: 823: 820: 817: 803: 793: 790: 780: 777: 766: 765: 764: 747: 736: 733: 730: 712: 709: 706: 692: 682: 679: 669: 666: 659: 648: 645: 642: 624: 621: 618: 600: 599: 598: 595: 585: 575: 573: 569: 565: 561: 556: 549: 541: 539: 535: 531: 526: 524: 520: 511: 505: 493: 488: 486: 482: 478: 474: 473:Giovanni Ceva 469: 467: 463: 440: 437: 434: 424: 421: 411: 408: 401: 391: 388: 378: 375: 368: 358: 355: 345: 342: 331: 330: 329: 319: 314: 312: 308: 304: 300: 299:line segments 296: 291: 238: 235: 225: 222: 212: 209: 202: 192: 189: 179: 176: 169: 159: 156: 146: 143: 132: 131: 130: 128: 124: 121:are known as 101: 91: 84: 79: 73: 69: 65: 57: 46: 39: 28: 22: 3166: 3141: 3120: 3105:cut-the-knot 3096:cut-the-knot 3088:at MathPages 3061: 3057: 3018: 3014: 3008: 2983: 2979: 2973: 2948: 2944: 2940: 2934: 2909: 2905: 2899: 2874: 2870: 2864: 2854: 2846: 2838: 2830: 2820: 2799: 2795: 2782: 2757: 2749: 2693: 2682: 2676: 2669: 2662: 2647: 2628: 2613: 2605: 2458: 2440: 2357: 2263: 2122: 2063: 2059:Affine space 2052: 1927: 1778: 1766: 1638: 1635: 1504: 1501:of triangle 1496: 1365: 1362:of triangle 1353: 1350: 1212: 1101: 978: 762: 596: 581: 568:affine plane 557: 550: 547: 534:cross-ratios 527: 522: 518: 509: 503: 489: 476: 470: 455: 315: 307:affine plane 292: 253: 99: 77: 67: 61: 55: 37: 2802:(1): 39–44. 763:Therefore, 494:(the lines 282:is between 3184:Categories 2741:References 1860:such that 1645:BC, AC, AB 496:AD, BE, CF 462:concurrent 458:AD, BE, CF 326:BC, AC, AB 86:AO, BO, CO 81:, let the 3173:EMS Press 3143:MathWorld 3035:123870381 2965:233413469 2650:simplexes 2616:simplexes 2580:λ 2570:λ 2558:¯ 2545:¯ 2516:λ 2506:λ 2494:¯ 2481:¯ 2415:λ 2405:λ 2393:¯ 2380:¯ 2335:→ 2316:λ 2307:→ 2288:λ 2244:→ 2225:λ 2216:→ 2197:λ 2188:→ 2169:λ 2165:− 2160:→ 2106:≠ 2097:λ 2087:λ 2077:λ 2033:→ 2014:λ 2005:→ 1986:λ 1977:→ 1958:λ 1949:→ 1898:λ 1885:λ 1872:λ 1842:λ 1829:λ 1816:λ 1785:collinear 1749:¯ 1731:¯ 1706:¯ 1693:¯ 1618:− 1609:¯ 1596:¯ 1582:⋅ 1576:¯ 1563:¯ 1549:⋅ 1543:¯ 1530:¯ 1479:− 1470:¯ 1457:¯ 1443:⋅ 1437:¯ 1424:¯ 1410:⋅ 1404:¯ 1391:¯ 1319:¯ 1306:¯ 1292:⋅ 1286:¯ 1273:¯ 1259:⋅ 1253:¯ 1240:¯ 1178:△ 1154:△ 1137:¯ 1124:¯ 1067:△ 1043:△ 1026:¯ 1013:¯ 944:△ 920:△ 889:△ 881:− 864:△ 840:△ 832:− 815:△ 798:¯ 785:¯ 728:△ 704:△ 687:¯ 674:¯ 640:△ 616:△ 570:over any 429:¯ 416:¯ 402:⋅ 396:¯ 383:¯ 369:⋅ 363:¯ 350:¯ 309:over any 303:collinear 301:that are 230:¯ 217:¯ 203:⋅ 197:¯ 184:¯ 170:⋅ 164:¯ 151:¯ 72:triangles 3064:: 1–18. 2850:Follows 2698:See also 2685:polygons 2633:)-face ( 1741:′ 1726:′ 1669:D, E, F' 1663:crosses 1655:and let 1651:meet at 485:Zaragoza 466:parallel 318:converse 90:vertices 52:outside 3175:, 2001 3000:2690569 2926:2300222 2891:2322390 2274:A, B, C 1805:A, B, C 1781:A, B, C 1641:D, E, F 564:vectors 322:D, E, F 123:cevians 105:D, E, F 34:inside 3033:  2998:  2963:  2924:  2889:  2770:  2618:using 1795:, the 1769:F = F’ 1649:AD, BE 544:Proofs 523:cevian 492:cevian 3031:S2CID 2996:JSTOR 2961:S2CID 2922:JSTOR 2887:JSTOR 2792:(PDF) 2635:facet 1793:plane 572:field 456:then 311:field 83:lines 2768:ISBN 2450:and 2135:and 1928:and 1102:and 983:and 562:and 519:Ceva 460:are 286:and 3154:at 3103:at 3094:at 3066:doi 3023:doi 2988:doi 2953:doi 2949:128 2914:doi 2879:doi 2764:210 2672:+ 1 2665:+ 1 2631:– 1 2529:and 2061:). 1799:of 1505:BCF 1499:AOD 1366:ACF 1360:BOE 555:. 510:DEF 502:), 100:ABC 78:ABC 62:In 56:ABC 38:ABC 3186:: 3171:, 3165:, 3140:. 3062:22 3060:. 3056:. 3029:. 3019:72 3017:. 2994:. 2984:68 2982:. 2959:. 2947:. 2920:. 2910:34 2908:. 2885:. 2875:95 2873:. 2808:^ 2800:11 2798:. 2794:. 2766:. 2691:. 2456:. 2453:FB 2447:AF 2343:0. 2270:AB 2266:CF 2137:OC 2133:AB 2109:0. 1771:. 1665:AB 1661:CO 1657:F' 1621:1. 1508:, 1369:, 989:BC 574:. 540:. 487:. 313:. 275:FB 273:/ 271:AF 257:XY 239:1. 129:, 118:CF 116:, 114:BE 112:, 110:AD 66:, 3146:. 3129:. 3074:. 3068:: 3037:. 3025:: 3002:. 2990:: 2967:. 2955:: 2941:n 2928:. 2916:: 2893:. 2881:: 2776:. 2670:k 2663:k 2658:k 2654:k 2629:n 2624:n 2591:. 2584:C 2574:A 2564:= 2554:A 2551:E 2541:E 2538:C 2520:B 2510:C 2500:= 2490:C 2487:D 2477:D 2474:B 2426:, 2419:A 2409:B 2399:= 2389:B 2386:F 2376:F 2373:A 2340:= 2331:B 2328:F 2320:B 2312:+ 2303:A 2300:F 2292:A 2249:. 2240:B 2237:F 2229:B 2221:+ 2212:A 2209:F 2201:A 2193:= 2184:C 2181:F 2173:C 2156:O 2153:F 2129:F 2125:X 2101:C 2091:B 2081:A 2066:O 2055:X 2038:, 2029:C 2026:X 2018:C 2010:+ 2001:B 1998:X 1990:B 1982:+ 1973:A 1970:X 1962:A 1954:= 1945:O 1942:X 1913:, 1910:1 1907:= 1902:C 1894:+ 1889:B 1881:+ 1876:A 1846:C 1838:, 1833:B 1825:, 1820:A 1801:O 1789:O 1745:B 1738:F 1723:F 1719:A 1712:= 1702:B 1699:F 1689:F 1686:A 1653:O 1615:= 1605:B 1602:D 1592:D 1589:C 1572:C 1569:O 1559:O 1556:F 1539:F 1536:A 1526:A 1523:B 1503:△ 1482:1 1476:= 1466:A 1463:E 1453:E 1450:C 1433:C 1430:O 1420:O 1417:F 1400:F 1397:B 1387:B 1384:A 1364:△ 1336:, 1333:1 1330:= 1326:| 1315:A 1312:E 1302:E 1299:C 1282:C 1279:D 1269:D 1266:B 1249:B 1246:F 1236:F 1233:A 1225:| 1198:. 1191:| 1187:O 1184:C 1181:B 1174:| 1167:| 1163:O 1160:A 1157:C 1150:| 1143:= 1133:B 1130:F 1120:F 1117:A 1087:, 1080:| 1076:O 1073:B 1070:A 1063:| 1056:| 1052:O 1049:C 1046:B 1039:| 1032:= 1022:A 1019:E 1009:E 1006:C 985:O 981:A 964:. 957:| 953:O 950:A 947:C 940:| 933:| 929:O 926:B 923:A 916:| 909:= 902:| 898:D 895:O 892:C 885:| 877:| 873:D 870:A 867:C 860:| 853:| 849:D 846:O 843:B 836:| 828:| 824:D 821:A 818:B 811:| 804:= 794:C 791:D 781:D 778:B 748:. 741:| 737:D 734:A 731:C 724:| 717:| 713:D 710:A 707:B 700:| 693:= 683:C 680:D 670:D 667:B 660:= 653:| 649:D 646:O 643:C 636:| 629:| 625:D 622:O 619:B 612:| 592:O 588:O 553:O 515:O 508:△ 500:O 441:, 438:1 435:= 425:A 422:E 412:E 409:C 392:C 389:D 379:D 376:B 359:B 356:F 346:F 343:A 288:B 284:A 280:F 266:Y 262:X 236:= 226:A 223:E 213:E 210:C 193:C 190:D 180:D 177:B 160:B 157:F 147:F 144:A 98:△ 94:O 76:△ 54:△ 50:O 36:△ 32:O 23:.

Index

Ceva (disambiguation)


Euclidean geometry
triangles
lines
vertices
cevians
signed lengths of segments
affine geometry
line segments
collinear
affine plane
field
converse
concurrent
parallel
Giovanni Ceva
Yusuf Al-Mu'taman ibn Hűd
Zaragoza
cevian
Menelaus' theorem
cross-ratios
projective duals
barycentric coordinates
vectors
affine plane
field
left-hand side
Menelaus's theorem

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