[理工] [工數]- 白努力!! 可以幫忙檢查一下嗎沒解答^^!!

[topee (eason)]

y'-y =  y^2


dy-ydx=y^2dx


除y^2


y^-2dy - y^-1dx = dx


令u= y^1-2 =y^-1


du = (1-2)y^-2dy


-du-udx = dx

du+udx = -dx

(D+1)u = -1

u  = c1e^-x
  h

u  = (1-D)(-1)
  p

   = -1

1/y = c1e^-x-1

y=(c1e^-x-1)^-1

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推 WinAVI:這題不用白努力 直接分離變數就可以囉
→ topee:題目好像有給指定