$\int_0^{\infty}\:\:\left(-\:\frac{sen\:x}{x}\right)\:dx$

$\left(8x-5y^2+12a-7b\right)^2$

$\left(-xy-xz-yz\right)\left(x+y+z\right)$

$5a^4b^5+8^a-4a^4b^5-8+3a^4b^5$

$x\left(8a^3b^2\right)\left(-15a^2b^3\right)$

$x^4-2^3+8x-15$

$\lim_{x\to7}\left(\frac{x^2+3x-70}{x-7}\right)$