Question

Simplify: ((1/x+h)-(1/x))/h

Answer 1

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

By multiplying the numerator and denominator by x(x + h):
[1/(x + h) - 1/x]/h
= {x(x + h) * [1/(x + h) - 1/x]}/[hx(x + h)]
= [x - (x + h)]/[hx(x + h)]
= (x - x - h)/[hx(x + h)]
= -h/[hx(x + h)]
= -1/[x(x + h)].

http://answers.yahoo.com/question/index?qid=20110122181251AAAr2zz

Answer 2

Again do the top part which results "h" since 1/x cancels each other
then h divided by h is 1 :D