$\int\frac{5x+15}{x^2-x-6}dx$

$\frac{3}{2}a-\frac{1}{4}a$

$\frac{3x^3+6x^2-x+2}{x+1}$

$\sqrt[3]{4-3}$

$\lim_{x\to0}\left(\frac{3}{1+2e^x}\right)$

$\frac{6}{x^2-x-6}-\frac{4}{x^2-2x-3}$

$\sin^2\left(-\frac{\pi}{3}\right)+\cos\left(\frac{17\pi}{6}\right)\sec\left(\frac{\pi}{6}\right)$