$\lim_{x\to0}\left(\frac{\arctan\left(x^2\right)}{4x^3-1}\right)$

$\frac{\csc\left(a\right)}{\sin\left(a\right)}-\frac{\cot\left(a\right)}{\tan\left(a\right)}$

$2\:-\:31\:+\:89\:+\:-39\:-\:8$

$y=\left(2+\frac{1}{x}\right)^8$

$x^9-1$

$a^3+\frac{1}{a^3}$

$\int\frac{9t^{2}}{\sqrt{49-t^{2}}}dt$