## Calculus (3rd Edition)

For $\int x \cos (x^2)dx$, we can use the substitution method. For $\int x \cos (x)dx$, we can use the Integration by Parts method. For $\int x^2 e^x dx$, we can use the Integration by Parts method. For $\int x^2 e^x dx$, we can use the substitution method.