$-\cot\left(\frac{5\pi}{6}\right)+\cot\left(\frac{\pi}{6}\right)$

$\int\frac{x}{\left(x-1\right)\left(x+1\right)\left(x+2\right)}dx$

$\int_9^{\infty}\left(-9x^{-\frac{2}{5}}\right)dx$

$\int\frac{4x^2+3x-4}{x^3+x^2-2x}dx$

$-\left|-19\right|$

$\left(2b+6\right)\left(2b+20\right)$

$\int_1^1\left(12x^{-1}\right)dx$