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Math Help - Integration by parts.

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    Integration by parts.

    I know this integral is an integration by parts, but what is the correct approach to breaking it up so that it becomes solvable?

    \int{x^5sin(x^3)}
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    Quote Originally Posted by gammaman View Post
    I know this integral is an integration by parts, but what is the correct approach to breaking it up so that it becomes solvable?

    \int{x^5sin(x^3)}
    u=x^3 \implies du=3x^2dx and

    dv=x^2\sin(x^3)dx \implies v=-\frac{1}{3}\cos(x^3)

    You should be able to finish from here
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    Thanks, but according to my notes

    u=1/3x^3
    du=x^2
    dv=3x^2sin(x^3)
    v=-cos(x^3)

    does this make sense? Your way seems much more logical.
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  4. #4
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    Quote Originally Posted by gammaman View Post
    Thanks, but according to my notes

    u=1/3x^3
    du=x^2
    dv=3x^2sin(x^3)
    v=-cos(x^3)

    does this make sense? Your way seems much more logical.
    You will get the same answer either way. If you write them out you will see that they are equivilent.

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