How do I find the limit, as h approaches 0, of ((4/(2+h)) - 2) / h

I used Wolfram Alpha in hopes of getting help there, but I don't understand the factoring between the first and second steps.

Here's the link to the page I used:

http://www.wolframalpha.com/input/?_=1332202782830&i=lim+((4%2f(2%2bh))+-+2)+%2f+h+as+h+-%3E+0&fp=1&incTime=true

Any help would be greatly appreciated.

[4/(2+h)-2]/h = = [4- 2(2+h)]/[h(h+2)] = (4-4-2h)/[h(2+h)] = -2h/[h(2+h)] = -2/(h+2)

lim h->0 -2/(h+2) = -1

Think first ! This algebra is 3rd grade ! And you are doing limits? Really?

It's not "condescension". You are not ready for this math. Go back 7 or 8 grades!

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