$\left(5a^2+7x^3\right)^2$

$\left(\frac{m^4n^{-2}}{r^3}\right).\left(\frac{m^{-3}n^2}{r}\right)^2$

$\frac{5a-b}{4\sqrt{2ab}+3\sqrt{a}}$

$-85\:nr024-1.jpg\:\left(-5\right)\:\:\:$

$\left(3\:x^5\:+4\:y^7\right)^2$

$+\frac{\frac{\cos a}{\sin a}}{1-\frac{\sin a}{\cos a}}$

$49x^2-36x^2$