$2\left(4\right)+2\left(2\right)$

$\frac{-20u^5+37u^3-8u^2-15}{4u^2-5}$

$\frac{\cos\left(x-y\right)}{\sin\left(x\right)\cdot\cos\left(y\right)}$

$\lim_{x\to0}\left(\frac{2-\left(1+2x\right)\:ln\left(1+2x\right)}{3x^3+x}\right)$

$\frac{1}{x}+1$

$m^5-40m^2+144m$