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Suppose that a random variable X is a discrete variable with the following distribution law P(X=k)=c/2^k, k= 0, 1, 2, . . . , Find the value of the constant c. (Using the normalization property of the distribution law)

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Answer:

The normalization property of the distribution law states that the sum of probabilities of all possible outcomes must equal 1. In this case, we have:

P(X=k) = c/2^k, for k = 0, 1, 2, ...

To find the value of the constant c, we need to use the normalization property:

∑ P(X=k) = ∑ c/2^k = c/2^0 + c/2^1 + c/2^2 + ... = 1

To simplify this expression, we can use the formula for the sum of an infinite geometric series:

∑ a*r^n = a/(1-r), where a is the first term, r is the common ratio, and n goes from 0 to infinity.

In this case, a = c, r = 1/2, and n goes from 0 to infinity. So we have:

∑ P(X=k) = ∑ c/2^k = c/2^0 + c/2^1 + c/2^2 + ... = c/(1-1/2) = 2c

Setting this expression equal to 1, we get:

2c = 1

c = 1/2

Therefore, the value of the constant c is 1/2.

Explanation:

User Gayan Kalhara
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