Can someone please explain to me what is happening from step A to step B in the attached diagram of a Full-Wave rectified Waveform ??
Ok, he's applying the limits, but from where did he get the "-1"s?
Attached is also my working for those steps.
Any help would be appreciated.
Reference link: Full-Wave Rectified Waveform Help for Fourier Series, Computer Science, Homework Help - Transtutors.com
Another quick question. Why should there be a minus in front of Vm/pi in step A ?
Also, cos(2n pi - pi) gives -1, but then there is the other -1 we found earlier, so wouldn't that make -2 in the last step ?? -1-1= -2