$\cot^2\left(x\right)+\frac{1}{\tan\left(x\right)\cot\left(x\right)}=\csc^2\left(x\right)$

$\int cos^5\left(3x\right)sin^2\left(3x\right)dx$

$\frac{1}{2}x-\left\{0,5-\left[0,25x-\left(\frac{1}{4}+x\right)\right]\right\}$

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

$\lim_{x\to5}\left(\frac{x^2+3x+2}{x-5}\right)$

$x+6>2\left(x+1\right)-3\left(x-2\right)$

$\frac{d}{dx}\frac{x+y}{x-y^2}=x$