$2\pi\int_0^3x\left[-\frac{x^3}{2}+x^2+x+3\right]dx$

$\left(\frac{5}{2}x-4\right)\left(\frac{3}{2}x-4\right)$

$x^2-\frac{2}{9}x$

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

$\lim_{x\to\infty}\left(\frac{v-1-\sqrt{v^2-7}}{v-4}\right)$

$\left(\frac{1}{2}y+6\right)^3$

$2x+3y-2y-x$