$\left(\frac{2}{3}x^4-\frac{1}{5}y^5\right)\left(\frac{2}{3}x^4+\frac{1}{5}y^5\right)^2$

$3a+5\cdot3a+5$

$\frac{d}{dx}\left(\ln\left(\tan\left(4x\right)+\sec\left(4x\right)\right)\right)$

$\left(\frac{1}{2}a+3\right)\left(\frac{1}{2}a-3\right)$

$\frac{\left(3+n\right)}{2^{\left(n+2\right)}}$

$\frac{8}{x^2-4x-12}$

$x\cdot\frac{1}{y}$