Differentiate (x+1)^1/2 from first principles

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auru
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Homework Statement



Differentiate (x+1)^1/2 from first principles with respect to x.

Homework Equations



f'(x) = Lim h→0 [f(x+h) - f(x)]/h

The Attempt at a Solution



f'(x) = Lim h→0 [f(x+h) - f(x)]/h
f'(x) = Lim h→0 [(x+h+1)^1/2 - (x+1)^1/2]/h

I'm unsure how to simplify from there.
 

Discussion

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Use the equality

[tex](x-a)(x+a)=x^2 - a^2[/tex]

to simplify the limit.
 
Simplify the fraction, let h go to zero and you're done.
 
I've done it now, thanks!