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

$\lim_{x\to0}\left(\frac{x^2+6}{x^2-5x+6}\right)$

$\sqrt[4]{16x^d}$

$dy=e^{-3x}dx$

$2y^2-3y+y^2$

$\lim_{x\to1}\left(\frac{e^{2\cdot\left(x-1\right)}-1}{\sqrt{4x^2-5x+1}}\right)$

$\lim_{x\to-1}\left(\frac{2x^2+x}{x+1}\right)$