$\frac{9-x^2}{3+x}$

$6\cdot\left(-3\right)\cdot9\cdot\left(-10\right)$

$\int\left(t^8+8\right)^4t^7dt$

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

$3-9\cdot6+4$

$\int\frac{2x^2\:+\:13}{\left(1-x\right)\left(x^2\:+4\right)}dx$

$\frac{1}{\sin\left(\frac{y}{2}\right)\cdot\cos\left(\frac{y}{2}\right)}$