$7\cdot\left(-1\right)\cdot4$

$\int_1^{\infty}\left(\frac{1}{4x+8+x^2}\right)dx$

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

$\frac{m+n}{2m+2n+4}-\frac{2}{m^2+2mn+2m+2n+n^2}$

$\frac{dy}{dx}=\frac{\left(y+2\right)}{\left(3y+4\right)}$

$3 x ^ { 5 } - 2 x ^ { 2 } + 9 x ^ { 4 } - 5 x + 3$

$2x+7\le4-x$