$$\frac{3m^{-4}}{m^3}$$

$$5x-3^2$$

$$\frac{8b}{10-\sqrt{b}}$$

$$\left(a^{3}+b^{3}\right)+-8\left(a^{3}-b^{3}\right)$$

$$x^2-20x+21=0$$

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

$$\left(6x^2\right)^2-2\left(6x^2\right)\left(\frac{1}{2}xy\right)^2+\left(\frac{1}{2}xy\right)^2$$