$4x^2+9y^2=72$

$\int\left(4\left(8x+12\right)^2\right)dx$

$\frac{1-cos\left(x\right)}{1+cos\left(x\right)}\left(\cot\left(x\right)-\csc\left(x\right)\right)^2$

$\lim_{x\to1}\left(x-5\right)$

$\int\frac{-9}{\left(x+5\right)^2\left(x-1\right)}dx$

$\left(2xy-a\right)\left(2xy-a\right)$

$\frac{1}{4}-\frac{1}{4}\cos\left(2x\right)=\frac{1}{8}\sin\left(x\right)^2$