$\lim_{x\to0}\left(\frac{1-\cos\left(x\right)}{x+5x^2}\right)$

$25x-30y-5x-10y$

$\int tsin\left(5t\right)dt$

$\frac{\tan\left(x\right)+3\sin\left(x\right)+2}{\tan\left(x\right)-3\sin\left(x\right)+1}=2$

$\int6x^3e^{2x}dx$

$\int\left(\frac{x^2}{\left(8+x^3\right)^4}\right)dx$

$\frac{dr}{d\theta\:}+rtan\theta\:=8sec\left(\theta\:\right)$