$\int_1^{\infty}\left(\frac{1}{1+cosx}\right)dx$

$x^2+18x+2$

$\frac{1}{\sin\left(x\right)\cos\left(x\right)}-\frac{1}{\cos\left(x\right)}=\frac{\cos\left(x\right)}{\sin\left(x\right)}$

$\lim_{n\to\infty}\left(\frac{n+2\sqrt{n}}{n^2}\right)$

$\frac{dy}{dx}=\frac{1}{2}x+1$

$\frac{dy}{dx}=\frac{\sec^2\left(x\right)}{1+2y}$

$-x^2-x^2+x^2$