$7\left(7c\right)$

$\frac{dy}{dx}=\frac{y^2+2y}{x^2}$

$\frac{du}{dx}=-3u-1+x^3$

$\lim_{x\to0}\left(\frac{x^2\cdot sin\left(bx\right)+ax+tan\left(2x\right)}{x^3}\right)$

$-50m-50m+50m-50m-50m-50m-50m$

$43mx^2+7mx^2-17mx^2-13mx^2$

$\lim_{x\to\infty}\left(\frac{\sqrt[10]{x}}{\ln\left(x\right)}\right)$