Find the differential dy of y=cos(x)

Find the derivative

$\frac{d}{dx}\left(2x^2+3y^2-4xy=36\right)$

Find the derivative

$\frac{d}{dx}\left(x^2-y^2=25\right)$

Find the derivative

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

Find the derivative

$\frac{d}{dx}\left(sinx^{lnx}\right)$

Find the derivative

$\frac{d}{dx}x^{cosx}$

Find the derivative

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

Find the derivative

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