$\lim_{x\to infinity}\left(\frac{x+2x^{\:3}}{1+x^3}\right)$

$\left(x^3-4x+3x^2\right):\left(x-3\right)$

$\int\frac{x^2+x}{\left(x^2+4\right)\left(x+2\right)}dx$

$\frac{\sec\:\left(x\right)}{1+\csc\:\left(x\right)}$

$20^2-4^2$

$\lim_{x\to1}\left(\frac{x^3-5x^2+7x-3}{x^2+3x+2}\right)$

$\left(-10\right).\left(-9\right).\left(+3\right)$