$\left(2a\right)\left(-a^2\right)\left(-3a^3\right)\left(4a\right)$

$\left(r^9s^6-r^6s^{12}\right)$

$6-4\cdot\left(8-5\right)-16$

$6\left(\frac{x^4}{81}\right)\left(\frac{1}{x^6}\right)$

$\int\frac{t^2}{\sqrt{25-t^2}}dt$

$9x^2-12+16$

$3a^3\:b\:c^2\:cuando\:a=2\:b=-1\:y\:c=3$