$x^2\cdot x^7$

$\sqrt[3]{81b^7}$

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

$3\ln\left(v\right)+\frac{1}{2}\ln\left(d\right)-4\ln\left(d^2+1\right)$

$\frac{1}{\left(k+n\right)\left(n+k+1\right)}$

$-500\:-\:400$

$\left(\sqrt{\sqrt[3]{\sqrt[5]{3^{15}}}}\right)^2$