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    it looks like both a and c are the right answrs
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    (Original post by WarriorOfPeace)
    it looks like both a and c are the right answrs
    What conditions have to be satisfied for a function to be a pdf? A cdf?
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    for the pdf

    If it's such that c =2 then cdf is x^2 and c=0.5 then the cdf is 0.25x^2
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    (Original post by WarriorOfPeace)


    for the pdf

    If it's such that c =2 then cdf is x^2 and c=0.5 then the cdf is 0.25x^2
    What is the value of

     \displaystyle \int_0^2 c x dx ?

    What can you therefore deduce about the possible value of c?
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    (Original post by Gregorius)
    What is the value of

     \displaystyle \int_0^2 c x dx ?

    What can you therefore deduce about the possible value of c?
    not sure how to latex this? (cx^2 / 2 ) = 1 so c = 1/2 when the limits of 0 to 2 are used?
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    (Original post by WarriorOfPeace)
    not sure how to latex this? (cx^2 / 2 ) = 1 so c = 1/2 when the limits of 0 to 2 are used?
    So is c=2 possible? Is f_X still a p.d.f if c=2?
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    (Original post by Zacken)
    So is c=2 possible? Is f_X still a p.d.f if c=2?
    If I replace c with 2 from the start it works, no? C = 1/2 works
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    (Original post by WarriorOfPeace)
    If I replace c with 2 from the start it works, no? C = 1/2 works
    Are you sure that f_X(x) = 2x^2 between 0 \leq x \leq 2 and 0 \, everywhere else is a P.D.F?

    Check: Does \displaystyle \int_0^2 2x^2 \, \mathrm{d}x = 1?
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    As an additional check, one can note that F(2)=4 for a,b, which is impossible for a cdf.
 
 
 
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