SymPy Gamma

SymPy:

integrate (tan (x))

$\int \tan{\left(x \right)}\, dx$

integrate(tan(x), x)

Plot:

plot(-log(cos(x)))

Roots:

solve(-log(cos(x)), x)

$x =$

diff(-log(cos(x)), x)

$\frac{d}{d x} \left(- \log{\left(\cos{\left(x \right)} \right)}\right) =$

series(-log(cos(x)), x, 0, 10)

See what Wolfram|Alpha has to say.

Experiment with SymPy at SymPy Live.