$4a+4a$

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

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

$\int_2^3\left(x-2\right)e^{2x}\:dx$

$9+x=52$

$\left(5xy^2-1\right)\left(5xy^2+1\right)$

$\int\frac{-8am}{z^4}dz$