$x^2.\:2x$

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

$\left(-7\right)\left|4\left(3-8\right)-5\left(8-5\right)\right|$

$3x+11\ge5\left(x+3\right)$

$\frac{d^4}{dx^4}\left(e^x\cos\left(2x\right)\right)$

$\left(3x^4\:\right)+\left(x^6-8\right)+\left(6x^2+12\right)$

$\sec\left(\arctan\left(\frac{\sqrt{x^2\:-9}}{3}\right)\right)$