A new method of resolving cubic equations ... Read, 6th May 1799 / [Sir James Ivory].

  • Ivory, James, Sir, 1765-1842.
Date:
[1805]
Catalogue details

Licence: Public Domain Mark

Credit: A new method of resolving cubic equations ... Read, 6th May 1799 / [Sir James Ivory]. Source: Wellcome Collection.

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    _ 16976 _ TO6l a ~~ ifio/3 b - 1584 160^3 - 39032 io>/3 99 i°\/3 4879 T — 43200^/3 54°°v/3 To find whether 2 can be expreffed by a furd as ^ V s/r' I write p — — 4879, q — 5400, and /• = 3 5 and I have thefe twcy equations, . — 4879 4- ^ V 9 (* i _ 3V* — 54oo (Jj — 3V I find, that 7, 17, and 41, are divifors of 4879. It is evident that + 7 would give v% negative: I therefore try 7> anc^ it does not fucceed : Neither does 4. 17 ; but trying — 17,1 find y* — 64, and confequently v zz + 8 : And —■ 8 is found to fucceed in the other equation; therefore p, rz — 17 v ~ — 8, and % — 8^* We have then, z — — v Therefore, x x X to 1 1 — 7 1 + v \f3 254/3 •v 4. 4/3 4T to > 1 H I ~ —)V 3 1061 , 17 - 4- 10 V3 8 4/3 8488 4-170 __ 8658 _ ” 99 , 17 792 4- 170 “ 962 104/3 3 v' 3 1061 7 104/3 254/3 5305 — 14 _ 5291 — ~ 99 7 495 — *4 481 104/3 254/3 1061 4T 104/3 94/3 _ 9549 — 410 _ 9J39 _ = 9 =Z I I 99 I9. 10V3 94/3 And fo the three roots are, 9, 11, and 19. FINIS.
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