Find the derivative $\frac{d}{dx}\left(5x^4-2x^3-x^2\right)$ using the sum rule

$\frac{d}{dx}\left(2x+1\right)^3$

$\frac{d}{dx}\left(\sqrt{\frac{x\left(x+2\right)}{\left(2x+1\right)\left(5x+3\right)}}\right)$

$\frac{d}{dx}\left(\arcsin\left(1-2x^2\right)\right)$

$\frac{d}{dx}\left(\sqrt{x+1}\right)$

$\frac{d}{dx}\left(x\sqrt{x^2+1}\right)$

Find the derivative

$\frac{d}{dx}\left(x^2+y^2\right)$

$\frac{d}{dx}\left(\arctan\left(x-\sqrt{1+x^2}\right)\right)$