$\csc\left(x\right)=\sin\left(y\right)+\cos\left(y\right)\cdot\cot\left(y\right)$

$\left(2x-y\right)dx=\left(x-3y\right)dy$

$\left(b-6\right)\left(b^2+6b+36\right)$

$\lim\:\:_{x\to\:\:0}\left(\frac{x\cdot\:\:\cos\:\:\left(\frac{\pi\:\:}{2}-x\right)}{1-\sec\:\:\left(x\right)}\right)$

$\int t^2\left(t^3+4\right)^2dx$

$\int\:\frac{\left(5x\right)}{x+1\:}dx$

$\left(\frac{3}{4}x^3-\frac{2}{3}x^4\right)^2$