$-7x^3+3x^2-5x$

$\sec\left(x\right)^2-\sec\left(x\right)+\tan\left(x\right)^2=\left(2\sec\left(x\right)+1\right)\left(\sec\left(x\right)-1\right)$

$\left[\left(6x\right)\:.\:\left(1.2\right)\right]^3$

$4\cos\left(-x\right)\cdot\cos\left(90+x\right)$

$4t+t$

$\int\:\frac{x}{\sqrt{x^2-16}}dx$

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