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Homework Help: Continuous prob. distribution

  1. Dec 19, 2003 #1
    i really dont know how to ue the Latex. it doesnt work although i try it for many times.

    so, im new to this chapter. maybe this question is easy to be solved, but i cant get it.

    a continuous random variable X has cumulative distribution as attached.
    the question is what is the value of alpha.
    i try doing like this but it doesnt give any answer though.

    F(-1) = 0 = (alpha)(-1)+(alpha)

    what is the working so that i can get the answer.
     

    Attached Files:

    Last edited: Dec 19, 2003
  2. jcsd
  3. Dec 19, 2003 #2
    blasphemy!!!!

    ok, if f(x) is a probability distribution I guess what matters the most is that:
    [tex]\int_D f(x)dx = 1[/tex]
    where D is the interval where f is defined (you didn't mentioned it in your question....)
     
  4. Dec 19, 2003 #3
    but that is a cumulative distribution.
    i copy the whole thing from the question.

    do i need to change it to probability density function first, then continue to work on it.
     
  5. Dec 19, 2003 #4
    oh....
    then alpha is 1/3 because as I remember [itex]f(\infty) = 1[/itex]
    and also the function is continuous....
     
  6. Dec 19, 2003 #5
    ok. thank you
     
    Last edited: Dec 19, 2003
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