$x\:-\:5\:+\:5x\:-\:12\:2x\:-\:6\:+\:3x\:-\:4$

$\left(w+4\right)\left(w-4\right)$

$\lim_{x\to0}\left(\frac{sin^2x-sinx^2}{cos\:x^2-1}\right)$

$\cot^2\left(\infty\right)=\cos^2\left(\infty\right)+\left(\cot\left(\infty\right).\cos\left(\infty\right)\right)^2$

$\frac{d}{dx}\:\sqrt[3]{x}+\sqrt[3]{xy}=4y^2$

$\frac{t^4-t^4}{x-y}$

$1.4+x=25\:$