Integration by Substitution: What Went Wrong in Solving \int x(x^{2}+5)^{75} dx?

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Homework Statement


I've come across the problem
[tex]\ \int x(x^{2}+5)^{75} dx[/tex]


Homework Equations





The Attempt at a Solution


Once going through the whole problem I got [tex]\ \frac{(x^{2}+5)^{76}}{76}+c[/tex]
but the text I have said the answer was, [tex]\frac{1}{152}(x^{2}+5)^{76}+c[/tex].
What did I do wrong?
 
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Did you try differentiating the answers to see which one gives you [tex]x(x^{2}+5)^{75}[/tex] ? Remember to apply the chain rule and that differentiating [tex]x^{2}+5[/tex] gives 2x
 
Presumably you let u= x^2+ 5. Then du= 2x dx. You forgot the "2".