$\lim_{x\to\frac{\pi}{2}}\left(tan\left(x\right)+\frac{1}{x-\frac{\pi}{2}}\right)$

$\left(8y^3\right)\left(-3\right)$

$27+125a^9$

$x^2-8=28$

$\frac{d}{dx}y^3-3xy+x^3=9$

$\frac{dy}{dt}=\left(ry\left(1-\frac{y}{1000}\right)\right)$

$\int\left(\frac{7}{x\sqrt{x^2-1}}\right)dx$