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Homework Help: Expected values

  1. Dec 16, 2004 #1
    ok, so to find the expected value of fy(Y) = 3(1-y)^2 for 0 <= 1 <= 1

    I thought the formula is y * fy(Y) which is the intgeral from 0 to 1 of y* 3(1-y)^2. right?

    the book says the answer is 1/4....but I get a whole number answer.......
  2. jcsd
  3. Dec 16, 2004 #2

    I did the integral of y*f(y) from 0 to 1 and got the answer 1/4...double check your calculation....This is what I did:

    Int[3*(1-y)^2] = 3*Int[y^3-2y^2+y] from 0 to 1
  4. Dec 16, 2004 #3
    oops, I forgot the y in the 1st integral expression
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