If you think about a sine wave, it is really showing a point on ... or you can use a trick to do one formula for each signal. Either way, you are going to need a timebase. You could also write ...

But don’t take our word for it: here’s a scope shot. The yellow line is the produced sine wave, and the purple is a FFT of the signal. Vertical bars are 20dBV, or a factor of ten. The first ...