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Homework Help: Fundamental theorem of calculus

  1. Jul 5, 2008 #1
    1. The problem statement, all variables and given/known data
    Evaluate each definite integral.

    ok I'm not sure how to do the integration sign, but... b=4, a=1 for (5yy^.5)+3y^.5)dy

    2. Relevant equations

    3. The attempt at a solution
    I'm not really sure what i'm doing wrong.

    i integrated...[tex]5y^2/2*y^(3/2)/(3/2)+3y^(3/2)/(3/2)

    then i plugged in stuff so...F(b)-F(a)...f(4)-(f1)

    I got (40*8/3+16)-(5/2*2/3+2) which gave me 357/3...the correct answer is 76 and I have no idea what I'm doing wrong, I've redone this problem 5 times and doublechecked to no avail :-(
  2. jcsd
  3. Jul 5, 2008 #2


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    [tex]\int_1 ^{4}(5yy^\frac{1}{2} + 3y^\frac{1}{2})dy \equiv \int_1 ^{4}(5y^\frac{3}{2} + 3y^\frac{1}{2})dy[/tex]

    Remember that y^m * y^n=y^(m+n)
  4. Jul 5, 2008 #3


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    And remember that you need to use that rule, because you can't integrate a product by taking the product of the integrals.
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