1. The problem statement, all variables and given/known data x(t) is input into a perfect lowpass filter with frequency response H(ω), having a bandwidth of BHz and a passband gain of 1. For B = (2πT)-1 Hz, calculate the ratio of the output signal energy to the input signal energy. 2. Relevant equations x(t) = Ae-|t|/T 3. The attempt at a solution I got |x(jω)| = A/(1+jω) Using input energy Wi = (1/pi)[itex]\int[/itex][itex]\infty[/itex]0|x(jω)|2 I got Wi to be A2/2 The output energy Wo = (1/pi)[itex]\int[/itex][itex]\infty[/itex]0|xo(jω)|2, where xo(jω) = X(jω)H(jω) but I'm unable to find any equation which links the frequency response to the bandwidth in order to get the output energy. I have that |H(ω)| = gain which in this instance is = 1. Is that all I need? I've a feeling I'm missing something very basic here. Any hints or clues appreciated!!