What is the first differential of f(x) = 1/(x(1+lnx) ?

1 Answer
Mar 3, 2017

-(2+lnx)/(x^2(1+lnx)^2

Explanation:

f(x) = 1/(x(1+lnx)

= (x*(1+lnx))^-1

Applying the power rule and the chain rule:

= -(x*(1+lnx))^-2 * d/dx(x*(1+lnx))

= -(x*(1+lnx))^-2 * x*(0+1/x)+(1+lnx)*1
[Product rule and standard differential]

= -(x*(1+lnx))^-2 * (1 +1 +lnx)

= -(2+lnx)/(x^2(1+lnx)^2