Encontrar la derivada de $\frac{d}{du}\left(yx\right)$

Encontrar la derivada

$\frac{d}{dx}\left(x\sinh x-\cosh x\right)$

$\frac{d}{dx}\left(\mathrm{sech}\left(-4x\right)\left(1-\ln\left(\mathrm{sech}\left(-4x\right)\right)\right)\right)$

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

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

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

$\frac{d}{dx}\left(x^3e^x\right)$

Encontrar la derivada

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