What is $\int x sin 3 x$ $int xsin3x$ ?

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Answer 1 · 2016-01-30T13:07:19

$- \frac{x^{2} cos 3 x}{3} - \frac{1}{9} sin 3 x + c$ $-(x^2cos3x)/3-1/9sin3x+c$

$\int x sin 3 x d x$ $intxsin3xdx$

$= x \int sin 3 x d x - \int [\frac{d}{d x} (x) \int sin 3 x d x] d x$ $=x intsin3xdx-int[d/(dx)(x) intsin3 xdx]dx$

$= - x^{2} \frac{cos 3 x}{3} - \int [\frac{cos 3 x}{3}] d x$ $=-x^2(cos3x)/3-int[(cos3x)/3]dx$

$= - \frac{x^{2} cos 3 x}{3} - \frac{1}{3} \frac{sin 3 x}{3} + c$ $=-(x^2cos3x)/3-1/3(sin3x)/3+c$

$= - \frac{x^{2} cos 3 x}{3} - \frac{1}{9} sin 3 x + c$ $=-(x^2cos3x)/3-1/9sin3x+c$

What is int xsin3x ∫xsin3xint xsin3x ?