$\left(\frac{3}{5}m^2n-\frac{1}{5}n^3\right)\left(\frac{3}{5}m^2n+\frac{1}{2}n^3\right)$

$3^{12}$

$\left(x+7\right)\left(x+5\right)\left(x+4\right)$

$\left(4b-7v\right)^2$

$30\left(x-\frac{5}{5}\right)+30\left(x-\frac{4}{2}\right)+30\left(x-\frac{3}{3}\right)+30\left(\frac{x}{30}\right)$

$\int\frac{t^3}{\left(2t^4+7\right)^3}dt$

$\int-7x^3\left(9x^4+10\right)^2dx$