推 ntust661:推 03/12 00:29
推 theater:推 03/12 01:00
※ 引述《theater (theater)》之銘言：
: (x-y^2)dx + y(1+x)dy = 0
: 不知道是否題目印錯,我解不出來
: 拜託了~看高手們有什麼見解
-2y-y =-3y
I = exp^∫-3/(x+1)dx = 1/(x+1)^3
(x-y^2)/(x+1)^3 dx + y/(1+x)^2dy = 0
ψ = y^2/2(x+1)^2 + f(x)
= y^2/2(x+1)^2 + ∫x/(x+1)^3 dx + g(y)
= y^2/2(x+1)^2 - (2x+1)/2(x+1)^2
ψ = c 為解
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