$\lim_{x\to0}\left(\frac{\sqrt{5+x^2}-\sqrt{2-x^2}}{x^2}\right)$

$\left(a^2d^2\right)\left(a^3d\right)$

$\int\frac{\left(2x+1\right)}{\left(x^2\:+\:1\right)^2}dx$

$+\frac{\frac{\cos a}{\sin a}}{1-\frac{\sin a}{\cos a}}$

$f\left(x\right)=\frac{x^2}{\left(x^2+5\right)^{-2}}$

$\left(x^4\right)^33\left(x^2\right)^2-1\left(-2x^2\right)^5\left(3x^2\right)^3$

$2x-1^2$