The probability function of a random variable is given by :
P(X = n) = [3^(n - 1) + 3]/(4^n) where n = 2,3,4,........infinity.
Find the expected value of X.
[Note: The following relation can be used without proof if you feel necessary:
Σ [nr^(n - 1)] where n from 1 to infinity and for 0 < r < 1 = ( 1- r)^(-2).]
Statistics
2010-09-09 5:59 am
回答 (1)
2010-09-09 6:51 am
✔ 最佳答案
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2010-09-08 22:51:21 補充：
http://img40.imageshack.us/img40/5691/66671859.png
2010-09-09 00:04:13 補充：
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