$x^9-\frac{1}{x}$

$y+y$

$4\left(2x\:+\:5\right)\:=\:8x\:+\:30$

$\left(2a^5\:-\:162a^3\right)$

$\sin\left(x\right)\cos\left(y\right)-\cos\left(x\right)\sin\left(y\right)$

$\sec\left(x\right)^4+\sec\left(x\right)^2-2=\tan\left(x\right)^2+2$

$\left(a+b\right)^2-\left(b-a\right)^2+\left(a-b\right)^2-a^2-4b^2$