$\frac{\left(\tan x+1\right)\left(tanx+1\right)-\sec^2\left(x\right)}{tanx}=2$

$+7^{12}-4^4$

$\left(-2\right)+5\left(-7\right)\cdot\left(8-6-1\right)$

$\frac{3x^5-4x^4-7x^2+5x-9}{x-2}$

$\frac{3}{ab}+\frac{2}{5ab}+\frac{2c}{7ab}$

$x^3\left(x^{-2}-2y\right)$

$7\cdot8\cdot6$