(adsbygoogle = window.adsbygoogle || []).push({}); 2r(s^2+1)dr + (r^4 + 1)ds = 0

2.book answer different than mine...book's answer: r^2 + s = c(1 -r^2 s)

3. 2r(s^2+1)dr =- (r^4 + 1)ds

-2r/r^4+1 dr = 1/s^2+1 ds

int -2r/r^4+1 dr = int 1/s^2+1 ds

with u substitution on left we have u = -2r, etc.

tan^-1 r^2 = - tan^ -1 s + c

tan^-1 r^2 + tan^-1 s = c

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# Homework Help: Separable First Order ODE

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