## [SOLVED] Covariance Question

Hi just a quick question, I have in my notes that:

$Cov(X,Y) = Var(X)$ for any $X$

Is this true? Wouldn't this mean that you could just work out the variance of $X$ and not bother with $Cov(X,Y)$?

Cheers.

Edit just realised that it was in fact :

$Cov(X,X) = Var(X)$ for any $X$, oops!