Let XXX be a random variable such that P(X=k)=C⋅2−kP(X=k) = C \cdot 2^{-k}P(X=k)=C⋅2−k for k=1,2,…k=1, 2, \dotsk=1,2,…. What is CCC?
111
1/21/21/2
222
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