$\left(\frac{5^{-1}}{5^{-2}+4\cdot5^{-3}}\right)^{-\frac{1}{2}}$

$\left(mn-4\right)^2$

$\lim_{x\to0}\left(\frac{5\cdot sin\left(4x^4\right)}{-2x}\right)$

$\int_0^5\pi\left(\left(x+3\right)^2\right)dx$

$\:\left(3x\:-\:4\right)\:\left(3x\:+\:4\right)\:=\:9x^2\:-\:8\:$

$8a^3+12ab^2+6ab^2+b^3$

$-6x-12+8y+16x$