How do you find the integral of x^3 * sin( x^2 ) dx?

1 Answer
Oct 11, 2015

I=1/2(-x^2cosx^2+sinx^2)+C

Explanation:

x^2=t => 2xdx=dt, x^3dx=1/2x^2 2xdx = 1/2tdt

int x^3 sinx^2 dx = 1/2 int tsintdt = I

u=t => du=dt

dv=sintdt => v=int sintdt= -cost

I=1/2[-tcost + int costdt] = 1/2(-tcost+sint)+C

I=1/2(-x^2cosx^2+sinx^2)+C