Thread: IS this the mean value of 2 functions?

Hello everyone.
In this ImageShack® - Online Photo and Video Hosting picture two lines before the end there is an equation with E{...}=E{...}=0.

For me this refers to the Expected Value of the two functions. What is the physical interpretation when two functions have an expected value of zero?

I would like to thank u in advance for your help

Best Regards
Alex

The expected value of the product is zero, which I assume the separate means are centered too?
If so then they have covariance zero, i.e., they are uncorrelated.