$\sqrt{a}+\sqrt{a+1}\cdot2\sqrt{a}+2\sqrt{a+1}$

$\left(x^2+y\right)^2\left(x^2-y\right)^2\left(x^2+y^2\right)^2$

$\frac{d}{dx}\left(\ln\left(x^2\right)-\arctan\left(\frac{x}{4}\right)\right)$

$7x\:-\:6\:+\:3x\:\le\:6x$

$\lim_{x\to\infty}\left(\frac{-5x+4}{-5x+1}\right)$

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

$4x^2b-6ab^2-8a^2b^2$