1. The problem statement, all variables and given/known data I know the rms of a half wave is half the peak value. But the peak value is not given to me. Instead, the V(t) function of 4cos(20pi(x)) is given. Also the period T = 100ms 2. Relevant equations vrms = vpeak/2 But the peak is not given! 3. The attempt at a solution Im not sure exactly how to integrate it in order to obtain the peak value and then divide it by 2 in order to get the rms. Much help is appreciated!