Find the first four non-zero terms of the Maclaurin series for $x^3 \sin(x^2)$.
I found the derivatives and got as following:
first derivative = $2x^3 \cos(x^2)$
second derivative = $-12x^3 \sin(x^2)$
third derivative = $-72x^3 \cos(x^2)$
when I used formula, I am substituting $x=0$ and getting all the first four terms as 0. Please help to solve this.