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Question from Omar, a student:

Hi my name omar ,
I have an exam tomorrow and i want answer of this question
Thank you
Q:the probability distribution function of a discrete random variable X is given by
P(X=x)=kx^3
For X=0,1,2,3
a)the value of the constant k .

Hi Omar,

For each $x$ calculate the value of $P(X = x),$ for example

\[P(X = 2) = k \times 2^3 = 8k.\]

Use the fact that

\[P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) = 1\]

and solve for $k.$

Penny

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