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Proving Operating Functions

  • #1

Homework Statement



If P(x)=x^(1/2)
show that P(x+h)-P(x)=h/[(x+h)^(1/2)+ x^(1/2)]

Homework Equations





The Attempt at a Solution




pls help me. I don't have any idea of this...
 

Answers and Replies

  • #2
Cyosis
Homework Helper
1,495
0
Try multiplying by:

[tex]\frac{\sqrt{x+h}+\sqrt{x}}{\sqrt{x+h}+\sqrt{x}}[/tex]
 
  • #3
Try multiplying by:

[tex]\frac{\sqrt{x+h}+\sqrt{x}}{\sqrt{x+h}+\sqrt{x}}[/tex]
Will i going to substitute it on the x variable? I don't know where it needs to be multiplied.
 
  • #4
HallsofIvy
Science Advisor
Homework Helper
41,794
925
"Multiply" doesn't mean substitute!

First form P(x+h) by replacing x with x+ h. Then subtract P(x) from that. That's what "P(x+h)- P(x)" means! Cyanosis is suggesting that you can get the final form you want by multiplying by
[tex]\frac{\sqrt{x+h}+\sqrt{x}}{\sqrt{x+h}+\sqrt{x}}[/tex]
 
  • #5
tnx for the explanation. :)
 
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