$\frac{dz}{dt}\left(x^2y-\sin\left(y\right)\right)\:\left(x=\sqrt{t^2+1}\right)\:\left(y=e^t\right)$

$\lim_{x\to0}\left(\frac{\sqrt{5x+9}-3}{y}\right)$

$\left(3x^4+5\right)\left(3x^4-1\right)$

$185-\left(-154\right)$

$25^{8^{-9^{-2^{-1}}}}$

$\left(9m-4n\right)^3$

$\left(3m\:-\:2n\right)\left(5m\:+n\right)$