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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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