$\int_0^2\left(x^3-3x^2+3x-\left(x\right)\right)dx$

$\lim_{x\to0}\left(\frac{\left(x+1\right)\cdot\left(2x-1\right)}{\left(2x+1\right)}\right)$

$\left(-\frac{4}{5}m^3n^2+5m^2n^3-7mn\right).\left(-m^2n^4+\frac{12}{5}mn\right)$

$\frac{1-\tan2\left(t\right)}{1+\tan2\left(t\right)}+1$

$21-87-21-43+43$

$\int\frac{2}{\sqrt[2]{9\:+\:x^2}}dx$

$\frac{3-3\cos^2\left(x\right)}{sin^2\left(x\right)}$