$5\sqrt{12}-19\sqrt{3}$

$-2m+3n-6:3m-8n:-5m+24y+2z$

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

$\frac{x}{3.1}=-5.6$

$\frac{x^5-x^4+x^2-2}{x^2+1}1$

$\csc\left(x\right)^2+2\csc\left(x\right)+1$

$\frac{d^2}{dx^2}x^5$