Question

What is `int xsin3x`?

Answer 1

`-(x^2cos3x)/3-1/9sin3x+c`

Explanation:

`intxsin3xdx`

`=x intsin3xdx-int[d/(dx)(x) intsin3 xdx]dx`

`=-x^2(cos3x)/3-int[(cos3x)/3]dx`

`=-(x^2cos3x)/3-1/3(sin3x)/3+c`

`=-(x^2cos3x)/3-1/9sin3x+c`