$\sec^4\left(x\right)-\tan^4\left(x\right)-1$

$4x^2+40x+9$

$\left(3x^3-\frac{1}{2}x^2+2x-1\right)+\:\left(-\frac{1}{4}+2x^2-5x^3+x\right)$

$\frac{3x^2y}{xy}$

$\left(a\:\:-\:\:15\right)\:\:\left(\:a\:\:+\:\:10\right)$

$2q\:=\:-14$

$\lim_{x\to\infty}\left(\frac{2x}{\sqrt[2]{x^2-1}}\right)$