$3a-4ab+2ac$

$\sqrt[3]{\frac{x\left(x-4\right)}{x^2+8}}$

$2x^2+4x-2.5=0$

$\lim_{x\to\infty}\left(\:\left(\frac{\sin\left(6x\right)\cos\left(e^{x^2+6}\right)}{x^6+6}\right)\right)$

$\frac{sec\left(x\right)-1}{tan\left(x\right)}=\frac{1-sec\left(x\right)}{tan\left(x\right)}$

$15x^2+16x+4=0$

$\left[\left(-18\right)\:-\:\left(+6\right)\right]\:-\:\left[\left(+18\right)\:-\:\left(-4\right)\right]$