$\int\:xe^{71x}dx$

$1+n=3$

$\left(-48\right)times\:48$

$x2+xy-12\:cuando\:x=3\:e\:y=\:-1$

$\int_0^{\infty}\left(\frac{\left(3x+1\right)\left(3x+2\right)}{\left(1+x\right)^2}\right)dx$

$\left(-3a^3b^4c\right)\left(7a^5b^3c^5\right)$

$\int\left(\left(2x-5x^2\right)\left(x^3+2x^2+9\right)\right)dx$