$$\left(\left(x-5\right)+x^2\right)\left(\left(x-5\right)-x^2\right)$$

$$\frac{3}{5}x^2\:y+5b^2$$

$$\lim_{x\to8.6}\left(\frac{x^2-\left(8.6\right)^2}{x-8.6}\right)$$

$$\frac{dy}{dx}\left(x^2+3xy+4y^2=32\right)$$

$$4b^2-9c^2$$

$$\frac{\frac{d}{dx}1}{\sqrt[3]{x^5}}$$

$$2x^3-x^2+3;\:x=-1$$