Find the derivative $\frac{d}{dx}\left(5x^3-6\cos\left(x\right)\right)$ using the sum rule

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

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

Find the derivative

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

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

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

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

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