Hi all. Consider the following demodulator: [itex]s(t)=A_c\cos[2\pi f_ct+\beta \sin(2\pi f_mt)][/itex] , [itex]\beta<1[/itex]. The delay line causes π/2 radians delay in phase. The problem is to find the output signal of the demodulator under the following assumptions: [itex]\cos(2\pi f_mT)\approx 1[/itex] [itex]\sin(2\pi f_mT)\approx 2\pi f_mT [/itex] T is the delay in time caused by the delay line which leads to π/2 radians delay in phase. It's not a homework, although once it was! What is the simplest way to solve this? Thanks in advance.