$x\frac{dy}{dx}+3y=\frac{3}{x}-3x$

$\frac{b^3}{b^6}$

$\int\left(x^2+1\right)^95x\:dx$

$\frac{\left(1-\cos\left(x\right)\right)\left(1+\cos\left(x\right)\right)}{\cos\left(x\right)}$

$\sin\left(\frac{4}{5}+\frac{8}{15}\right)$

$2x^2-6x+3$

$\lim_{x\to-\infty}\left(\frac{x^3-x^2-3x+2}{x^2-3x+2}\right)$