(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hey all. I'm having issues with a few Diff. Eq. problems. I think I'm screwing up at the point of u-substitution, but I do not know for sure.

2. Relevant equations

I'm evaluating: (x^{2}+ x^{3})*integral (x^{4}/(x^{4}+2x^{5}+x^{6})

3. The attempt at a solution

I eliminate x^{4}inside the integral and evaluate:

x*(x+1)*integral(dx/(x+1)^{2})

= x^{2}*(x+1)/-(x+1). Cancel out (x+1), and my answer is

= -x^{2}.

However, the back of the book says the answer should be x^{2}(positive). Can anyone point out as to what I'm doing wrong? I've gotten a few of these wrong, usually because they are in the denominator and I do u-substitution.

P.S.: If anyone has a link on how to use Latex Reference, it'd be greatly appreciated. I tried a few things and could not get it to work, for the life of me.

Latex text: [tex]y_2[/tex]

Many thanks.

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# Homework Help: Ordinary Diff Eq. - Help with Calculus

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