Question

find nth derivative of y=1-x/1+x

Answer 1

$y=\frac{1-x}{1+x}=\frac{2}{1+x}-1=2(1+x)^{-1}\\ \\\frac{dy}{dx}=2*(-1)(1+x)^{-1-1}\\\\\frac{d^2y}{dx^2}=2*(-1)(-2)(1+x)^{-1-2}\\ \\\frac{d^ny}{dx^n}=2*(-1)(-2)...(-n)(1+x)^{-1-n}=2(-1)^n\ n! (1+x)^{-(n+1)}$