A voltage v(t) which is a gaussian ergodic random process witha mean of zero and a varance of 4 volt² is measured by a meter which first square and then reads its dc component. The reading will be

The function shown in the figure

If f₁(t) ↔ F₁ (jω) and f₂(t) ↔ F₂(jω), then f₁(t)↔ f₂(t)

Parseval's theorem for energy tells that

The sampling of a function f(l) = sin 2pf₀t starts from a zero crossing. The signal can be detected if sampling time T is

If ξ f(t) = F(jω), ξf(t-a) =