SymPy Gamma

SymPy:

integrate (tan (x),(x,0,pi /2))

$\int\limits_{0}^{\frac{\pi}{2}} \tan{\left(x \right)}\, dx$

integrate(tan(x), (x, 0, pi/2))

See what Wolfram|Alpha has to say.

Want to compute something more complicated? Try a full Python/SymPy console at SymPy Live.