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

$\sqrt{2}-7\sqrt{2}+30\sqrt{2}-42\sqrt{2}$

$\frac{16}{1}+\frac{16}{1}$

$x^2=15x+54$

$4n+20=4$

$4y^2-24y$

$f\left(x\right)=\left(6x+5\right)\left(x^3-2\right)$