$\frac{1}{\tan\left(x\right)\csc\left(x\right)}=\cos\left(x\right)$

$x^4-2x^3-13^2+14x+24$

$\int\:\frac{5x^2+3x-1}{x^3-2x^2+x-2}dx$

$\left(3x^3-13x^2-13x+2\right)\left(3x+2\right)$

$25^2-30x+9$

$\int_0^{\frac{\pi}{4}}\frac{1}{x^4-1}dx$

$-\left(-2\right)+\left(+12\right)+4-3\left(-10\right)\left(-1\right)$