1 1
/ /
| |
| 3 | 3
| x *tan(x) dx = | x *tan(x) dx
| |
/ /
0 0
$$-{{4\,i\,\arctan \left({{\sin 2}\over{\cos 2+1}}\right)}\over{3}}-
{{2\,\log \left(2\,\cos 2+2\right)}\over{3}}-i\,{\it li}_{4}(-e^{2\,
i})-2\,{\it li}_{3}(-e^{2\,i})+2\,i\,{\it li}_{2}(-e^{2\,i})-{{7\,i
\,\pi^4}\over{720}}+{{i}\over{4}}$$
Ответ (Неопределённый)
[src]$$-{{8\,x^3\,\log \left(\sin ^2\left(2\,x\right)+\cos ^2\left(2\,x
\right)+2\,\cos \left(2\,x\right)+1\right)+16\,i\,x^3\,{\rm atan2}
\left(\sin \left(2\,x\right) , \cos \left(2\,x\right)+1\right)+12\,i
\,{\it li}_{4}(-e^{2\,i\,x})+24\,x\,{\it li}_{3}(-e^{2\,i\,x})-24\,i
\,x^2\,{\it li}_{2}(-e^{2\,i\,x})-3\,i\,x^4}\over{12}}$$