# Multiplying by a conjugate?

#### dimpledur

multiplying by a conjugate??

1. Homework Statement

I am dealing with a limit, however, I am not sure how to multiply by a conjugate when there are two variables and three terms on top. For example

lim [3h + sqrt( 2x +2h) - sqrt( 2x)] / h
h->0

i dont need help solving it, i just need to know how would we multiply it by a conjugate when there are more than 2 terms?

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#### Dick

Science Advisor
Homework Helper
Re: multiplying by a conjugate??

I don't know how you got that but lim h->0 3h/h=3. There. Now you only have two terms in the numerator.

#### cam875

Re: multiplying by a conjugate??

how did you get h=3?, I tried the problem aswell and got stuck.

#### Dick

Science Advisor
Homework Helper
Re: multiplying by a conjugate??

how did you get h=3?, I tried the problem aswell and got stuck.
I didn't get h=3. I got limit h->0 3h/h=3. That leaves you with figuring out limit h->0 (sqrt(2x+2h)-sqrt(2x))/h.

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