Find a primitive function for $3\sin x$3sinx.
You may use $c$c as a constant.
Find a primitive function for $3\cos x$3cosx.
You may use $c$c as the constant of integration.
Find the integral of $\sin5x$sin5x.
You may use $c$c as the constant of integration.
Integrate $\cos4x$cos4x.
You may use $c$c as the constant of integration.