$\sqrt[9]{27\cdot a^{18}\cdot b^6}$

$\left(15x^2y^52^7\right)\left(5xy^32^4\right)$

$-30\::\:-8$

$\left(\frac{2r^3}{7t^3}\right)^{-3}$

$\frac{\cos\left(x\right)+\tan\left(x\right)}{\cos\left(x\right)\cdot\tan\left(x\right)}=\cot\left(x\right)$

$5c+c$

$\:\int\:\frac{6x^2+22x-23}{\left(2x-1\right)\left(x^2+x-6\right)}dx$