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Question
Prove that V(aX) = a2V(X)
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Solution
L.H.S = V(ax)
= E(ax)2 – [E(ax)]2
= a2E(x2) – [aE(x)]2
= a2E(x2) – a2E(x)]2
= a2E(x2) – E(x)2]
= a2v(x)
= R.H.S
Hence proved.
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