Simplifying compound fractions

[datafiend]

Hi all,
I'm having a problem simplifying this:

[1/(1+x+h) - 1/(1+x)] / h

How do you get the common denominators for the top 2 fractions?

Thanks

 

[pickslides]

Maybe try to find a common denominator for 1+x+h and 1+x.

$(1+x+h)\times(1+h) = x^2+x(2+h)+1+h$

 

[MarkFL]

In the numerator, I would use:

$$\frac{1}{a}-\frac{1}{b}=\frac{b-a}{ab}$$

 

[datafiend]

mark,
thanks again!