What is the integral of cos(x) with respect to x?

Evaluate the integral.

$\int 2x^2\sin x^{3}dx$

Evaluate $\int \cos \left(3x\right)\cos \left(5x\right)dx$ using the product-to-sum identity.

Evaluate the integral.

$\int \frac{\cos 5x}{9+{\sin }^{2}5x}dx$

Evaluate the integral.

$\int \sqrt{2+\tan 3x}{\sec }^{2}3xdx$