$x\left(\frac{\sin\left(x\right)}{\cos^2x}\right)-\left(\frac{1}{\cos\left(x\right)}\right)\tan\left(x\right)=0$

$\frac{3}{4}\cdot8$

$\left(12x^2y\right)^{-1}$

$\left(\sqrt{x}\right)+x\cdot\left(\frac{1}{2\sqrt{x}}\right)$

$9u-11u$

$\frac{\left(x+y\right)^2-\left(x-y\right)^2}{xy}$

$8+5v+-7$