$\left(\frac{4x^2+6x^3}{x^2-2x}\right)^{-2}$

$\cos\left(x\right)\cot\left(x\right)-\sin\left(-x\right)$

$\int4x\left(\frac{5x^2}{3}-3\right)^5dx$

$\lim_{x\to\infty}\left(\frac{x\left(\cos\:\left(x\right)-1\right)}{\left(x^2+x+1\right)^{\frac{1}{2}}}\right)$

$\frac{15x-20}{5x+10}$

$\left(5a+7b-3c\right)\left(b-5c+2a\right)$

$4n^2+2n+6=0$