# Calc

posted by
**Brian** on
.

y=ln(x+1) +ln(x-1) find dy/dx

I have trouble with this problem since i'm not that familar with finding the derivative when they involve ln. Please show me how to solve this problem. I should have gotten 2x/(x^2-1)

The derivative of ln(x) is 1/x

So, you obtain

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

Adding the fractions gives you the desired answer 2x/(x^2-1) .