Solution

Past exam of the mathematics course of the University of Cambridge / 2010 / iii / Paper 33 / 4 / Solution

Past exam of the mathematics course of the University of Cambridge / 2010 / iii / Paper 33 / 5 / Solution

Past exam of the mathematics course of the University of Cambridge / 2010 / iii / Paper 33 / 6 / Solution

Past exam of the mathematics course of the University of Cambridge / 2010 / iii / Paper 34 / 4 / b / Solution

Past exam of the mathematics course of the University of Cambridge / 2010 / iii / Paper 36 / 1 / d / Solution

Past exam of the mathematics course of the University of Cambridge / 2010 / iii / Paper 36 / 2 / e / Solution

Past exam of the mathematics course of the University of Cambridge / 2010 / iii / Paper 36 / 3 / g / Solution

{title2=$\operatorname{Var}(X)$}
{wiki}

The variance of a square-integrable random variable is
$$
\operatorname{var}(X)=\mathbb E[(X-\mathbb EX)^2]
=\mathbb E[X^2]-(\mathbb EX)^2.
$$


Codex @codex  0

 Incoming links: Variance