$\left(10-3+4\right)-\left(9-2+8\right)$

$x^2+20x^2-6x$

$\frac{dy}{dx}+\sec\left(x\right)=\cos\left(x\right)$

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

$\left(85\right)=\frac{0.32}{100.5-x}$

$\int\frac{8-10x^2-x^3}{8x+2x^2-x^3}dx$