$$\frac{\left(x+y\right)^2-25}{\left(x+y\right)-5}$$

$$x^4-625$$

$$\frac{dy}{dx}\left(2x+3y=x+1\right)$$

$$2a\sqrt[3]{27x^3y}$$

$$\left(\sqrt{\sqrt{x}+\sqrt{y}-\sqrt{4\left(\sqrt{xy}\right)}}\right)$$

$$\left(a^4+b^4\right)\left(a^4-b^4\right)$$

$$\frac{\left(\frac{2}{5}\right)}{\left(\frac{5}{2}\right)\left(\frac{5}{2}\right)}^{-2}$$