Can anybody help me in evaluating this indefinite integral? I can't possibly find a workable substitution: $$\int \dfrac {t^4 \tan t}{2 + \cos t}dt$$
I have already tried substituting $\tan t=\frac{\sin t}{\cos t}$ and it ended up as $\int \frac {t^4\frac {\sin t}{\cos t}}{2+\cos t}~dt \Rightarrow \int \frac {t^4\sin t}{2\cos t + \cos^2 t}~dt$. Substitution fails from here.