$\frac{\sin\left(4x\right)}{\sin\left(2x\right)}\cdot\sin\left(2x\right)$

$cos^2\left(u\right)\left(sec^2\left(u\right)-1\right)=sen^2\left(u\right)$

$\int_5^{\infty}\left(\frac{1}{\sqrt{\left(x+1\right)}}\right)dx$

$\int\frac{1}{9+e^{-3x}}dx$

$\left(15m-12n\right)\left(15m+12n\right)$

$\left(m\frac{1}{3}\right)^{\frac{1}{5}}$

$28\left(3\right)$