Evaluate $\int x(7-5x^2)^5dx$ using u substitution

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Section 5.2

Evaluate $\int x(7-5x^2)^5dx$ using u substitution

Can somebody verify this solution for me?? Thanks


Let $u=7-5x^2$. Then $\frac{du}{dx}=-10x$ and so $\frac{du}{-10x}=dx$. Making these substitutions we get:

$\int x(7-5x^2)^5dx$

$=\int x(u)^5 \frac{du}{-10x}$

$=\frac{1}{-10} \int u^5du$

$=\frac{1}{-10} u^6 \frac{1}{6} + C$

$=\frac{-1}{60} u^6 +C$

$= \frac{-1}{60} (7-5x^2)^6 +C$