What is the derivative of ln(1+(1/x))?

1 Answer
Aug 30, 2015

d/dx(ln(1+(1/x))) = (-1)/(x(x+1))

Explanation:

Although you could use d/dx (ln(u)) = 1/u (du)/dx, the algebra will get messy that way.

Let's rewrite using properties of ln.

y = ln(1+(1/x)) = ln((x+1)/x)

= ln(x+1) - ln(x)

So

dy/dx = 1/(x+1) - 1/x = (-1)/(x(x+1))