$\left(\sec\left(x\right)\right)\left(\csc\left(x\right)-\cot\left(x\right)\cos\left(x\right)\right)$

$\lim_{x\to-\infty}\left(\frac{x^2-40}{x-5}\right)$

$x^2-2x+1+x-4+2x-8$

$\frac{sinx}{1-cosx}+cot\left(\frac{1}{2}\right)x$

$\frac{dy}{dx}=\frac{-x}{y},y\left(4\right)=3$

$\int\left(-3-2x^2+\frac{2x+9}{3-x^2}\right)dx$

$-3\left(-2\right)^2-5\left(-2\right)+4$