$9-8+7-6+5-4+3-2+1$

$\frac{\left(-9x-72\right)}{\left(x^3+8x^2\right)}$

$\frac { ( 0.02435 ) ( 53.125 ) } { ( 142.356 ) ( 0.189 ) }$

$\left(4x^2-3x+8\right)\cdot\left(2x-1\right)$

$\int_{-7}^{-3}\left(0.5\left(x+7\right)\right)dx$

$\lim_{x\to\infty}\left(\frac{1}{2}ln\left(x+1\right)-\frac{1}{4}ln\left(x^2+1\right)+\frac{1}{2}\arctan\left(x\right)\right)$

$9-x^2=0$