$\int\csc^{2}\theta\sec\thetad\theta$

$\lim_{x\to0}\left(\frac{e^x-e^{-6}-2x}{x-sin\left(x\right)}\right)$

$\frac{dy}{dx}=\frac{senx}{cosy}$

$\frac{5}{3}z-3=7$

$\left(8+b\right)\left(6+b\right)$

$\lim_{x\to\infty}\left(\frac{\ln x}{x-1}\right)$