Math Help - Integrate

1. Integrate

Integrate the following with respect to x

3 x squared

and,

cos 2 x

2. $
\begin{gathered}
\int {kx^n } = k\int {x^n } = k\frac{{x^{n + 1} }}
{{n + 1}} + C \hfill \\
\int {\cos (kx) = \sin (kx)/k + C} \hfill \\
\end{gathered}
$