Yes, that is the simple HOW.Multiply the voltage by the current and plot the result.

That gives you power.

But I was hoping to see Ham' come up with the "proofing" answer, since he went to such degree for proofing the plot of power (when pf=1) based on Pavg. The exercise, per se, was more a question of proofing the relationship of scalar and vector approaches using S, P, and Q (hint).