$\lim_{x\to1}\left(\frac{3\sin\left(x\pi\right)-\sin\left(3\pi x\right)}{x^3}\right)$

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

$\frac{\sin x-\sin^3x}{\cos^2x}$

$\:-49a^{10n}\:-\:\frac{b^{12x}}{81}$

$y=\:\frac{2x^2+3}{4x+2}$

$\frac{2}{3}\:x\:\frac{1}{1}$

$7\tan^2\left(x\right)+3\sec^2\left(x\right)$