$\int\left(\frac{\tan\left(ax\right)}{\cos\left(ax\right)}\right)dx$

$\int\frac{\left(x-3\right)}{sqrt\left(16+6x-x^2\right)}dx$

$\log\left(x-16\right)=2-\log\left(x-1\right)$

$m^2-13m$

$5x^3\sqrt{x^2}$

$\lim_{x\to3}\frac{9-x^2}{\cos\left(\frac{\pi}{2}x\right)}$

$\frac{1}{x^3}+\frac{1}{y^3}$