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Homework Help: Find the average of f(x)=sqrt(1-x) on the interval [-1,1]?

  1. Jun 10, 2010 #1
    Please show work. There was a negative sign that appeared in the solution and I don't know why.

    I know [tex]\sqrt{}(1-X)[/tex] can be rewritten as (1-X)^1/2 and then you use the power rule to integrate but that gives you



    My book shows


    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jun 10, 2010 #2


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    Science Advisor
    Homework Helper

    You integrate that by using the substitution u=1-x. So dx=(-du). Then use the power rule on the u integral. That's where the '-' sign comes from.
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