Finding A Relative Condition Number

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The discussion focuses on calculating the relative condition number for the function f(x) = sqrt(x+1) - sqrt(x). A user is unsure if their equation for the relative condition number is correct and whether they need to solve a limit as x approaches 0. Another participant confirms the equation appears correct but notes that the term "relative condition number" is not widely recognized. They suggest consulting a Wikipedia article for clarification and emphasize that the limit should be considered in terms of δx, not x. The conversation highlights the need for clear definitions in numerical analysis.
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Homework Statement
Find the relative condition number for f(x)=sqrt(x+1)-sqrt(x).
Relevant Equations
f(x)=sqrt(x+1)-sqrt(x).
Hm I'm new to these concepts, and I want to make sure I am on the right track, would the relative condition number be:

k=(x/2)((1/sqrt(x+1))-(1/sqrt(x))(1/(sqrt(x+1)-sqrt(x))). Or would I have to solve the limit as x approaches 0?

Thank you.
 
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I know condition number in numerical analysis but what is the concept or definition of "relative condition number" you say?
 
ver_mathstats said:
Homework Statement:: Find the relative condition number for f(x)=sqrt(x+1)-sqrt(x).
Relevant Equations:: f(x)=sqrt(x+1)-sqrt(x).

Hm I'm new to these concepts, and I want to make sure I am on the right track, would the relative condition number be:

k=(x/2)((1/sqrt(x+1))-(1/sqrt(x))(1/(sqrt(x+1)-sqrt(x))). Or would I have to solve the limit as x approaches 0?

Thank you.
  1. I'm reasonably sure your equation above is written correctly, but it's really hard to parse.
  2. I'm not familiar with the term "relative condition number," but this wikipedia article (https://en.wikipedia.org/wiki/Condition_number) provides a definition. The section titled "Several variables" defines the term "relative condition number."
  3. From the above definition, the limit is on ##\delta x##, not x.
 
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