$-\left\{-\left[-\left(a-b\right)\right]\right\}-\left\{\left[-\left(a+b\right)\right]\right\}$

$\lim_{x\to-2}\left(\frac{8}{4-x^2}-\frac{1}{2+x}\right)$

$-17\:-\:\left(-1\right)\:+\:1$

$3+-3+4+-4+5+-5+1$

$\int\left(\frac{4x^2+3}{\left(x-5\right)^3}\right)dx$

$\left(-5\right)\cdot\left(-3\right)+\left(-7\right)$

$-4r^2+3r^2+-6r^2-3r^2$