$9\:\left(-7\:+\:3c\right)\:+\:8c$

$\lim_{x\to-1}\left(\frac{x^3-x^2-2x}{\ln\left(x+2\right)}\right)$

$4x^4+10x^3-14x^2-22x+6$

$cos\:x\:\left(tan\:x\:+cot\:x\:\right)=cos\:x$

$\frac{cosx}{tanx}$

$2x^2-12+11$

$\lim_{x\to\infty}\left(\sqrt{1+\frac{3}{4}.\frac{1}{x}}\right)$