$\lim_{x\to0}\left(cos\left(x\right)^{cos\left(x\right)}\right)$

$\left(y+2cm\right)^3$

$-x^3+2x^2+9x-18$

$\sec\left(x\right)\cos\left(x\right)\sin\left(x\right)=\sin\left(x\right)$

$\left(8-z\right)^{\frac{2}{3}}-\left(\frac{16}{3}z-\frac{8}{3}z^2+\frac{20}{3}-\frac{10}{3}z\right)^{-\frac{1}{3}}$

$\left(x^3y^4\right)^2$

$18=n-18$