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Let X be a real-valued random variable with E[X] and E[X2] denoting the mean values of X and X2, respectively. The relation which always holds is

Let X be a real-valued random variable with E[X] and E[X2] denoting the mean values of X and X2, respectively. The relation which always holds is Correct Answer E(X<sup>2</sup>) ≥ (E[X])<sup>2</sup>

Concept:

E denotes the mean value of ‘X’

E denotes the mean value of X2

Also, the variance of Random variable ‘X’ is given as:

Var(X) = E(X2) – 2

Note: Variance is always non-negative, i.e.

E – 2 ≥ 0

∴ E ≥ (E)2

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