Re: [微積] 求解！

[Honor1984 (希望願望成真)]

※ 引述《rita42027 (CHIEN)》之銘言：
: http://i.imgur.com/zFZEmZf.jpg
: Question5.求解

x^3 + 3yx^2 + y^3 = 5

(x, y) = (1, 1)

[3x^2 + 6xy] + [3x^2 + 3y^2]y' = 0

=> y' = [- 3 - 6] / [3 + 3]

      = -3 / 2

[6x + 6y + 6xy'] + [6x + 5yy']y' + [3x^2 + 3y^2]y" = 0

=> y" = [-6 - 6 + 9 - 45/4] / [3 + 3]

      = -5 / 4

--
※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 111.249.198.160
※ 文章網址: https://www.ptt.cc/bbs/Math/M.1445275917.A.34E.html