Hey.. im having some problems with this homework question, i thought perphaps somebody can help me on it.(adsbygoogle = window.adsbygoogle || []).push({});

-- Let X be a random variable with probability mass function

x P(x)

-1 p

1 1 - p

Find the value of the constant C not equal to 1 such that E[c^X] = 1

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So this is my work so far. We have E[X] = 1 -2p and E[c^X] = 1 ...

E[X] = 1 -2p

E[c^X] = 1

then c^X = c^(1-2p) = 1 so...

c^(1-2p) = 1

I do the logarithms....

(1-2p)logc = log1

(1-2p)logc = 0

log c = 0

c = 1

but that is no true, since c cannot equal 1. What am i doing wrong?

The only other solution i can see is 1^(1-2p)^-1 =1/(1-2p)

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# Homework Help: Probability Theory - Expected Value.

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