$a^2-6ab+9b^2-2f$

$\frac{1-sin\left(x\right)}{\cos^2\left(x\right)}+\frac{1}{1-\sin\left(x\right)}=2sec^2\left(x\right)$

$\lim_{x\to0}\left(\frac{x\cdot\left(\tan\left(x\right)\right)^{-1}}{1-\cos\left(x\right)}\right)$

$\int4xe^{xy}dy$

$8x-\left(1\frac{1}{2}y+6z-2\frac{3}{4}x\right)-\left(-3\frac{3}{5}x+20y\right)-\left(x+\frac{3}{4}y+z\right)$

$y=x^{\left(\frac{1}{x}+2\right)^3}$

$-x\left(x+2x^5\right)$