# Question: Prove Theorem 5 6 by first determining E X and E X X

Prove Theorem 5.6 by first determining E(X) and E[X(X + 1)].

Theorem 5.6

The mean and the variance of the negative binomial distribution are

µ = k/θ and σ2 = k/θ(1/θ – 1)

Theorem 5.6

The mean and the variance of the negative binomial distribution are

µ = k/θ and σ2 = k/θ(1/θ – 1)

## Answer to relevant Questions

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