Question

me ajudem nesses 2 itens por favor.​

Answer 1

$\frac{d}{dx}(\frac{f}{g})=\frac{\frac{df}{dx}g-f\frac{dg}{dx}}{g^2}\\\\\frac{d}{dx}(\frac{senx}{1-csox})=\frac{[\frac{d}{dx}(senx)](1-cosx)-senx\frac{d}{dx}(1-cosx)}{(1-cosx)^2}\\\\=\frac{cosx(1-cosx)-senx(senx)}{(1-cosx)^2}\\\\=\frac{cosx-cos^2x-sen^2x}{(1-cosx)^2}\\\\=\frac{cosx-1}{(1-cosx)^2}\\\\=\frac{-1}{1-cosx}$

$\frac{d}{dx}u(v)=\frac{d}{dv}u(v).\frac{dv}{dx}\\\\\frac{d}{dx}(2x+1)^3=\frac{d}{d(2x+1)}(2x+1)^3.\frac{d}{dx}(2x+1)\\\\=3(2x+1)^2.2\\\\=6(2x+1)^2$