Combined sine, adjust phase and frequency Make a plot_ly plot, combining two sine waves with nearby frequencies through multiplcation. Give controls over the phase of the second sine wave. See what it does to the result.

Trig identity:

cos(α + β) = cos(α) cos(β) – sin(α) sin(β)

Rearranged:

sin(α) sin(β) = cos(α) cos(β) + cos(α + β)

So if one wave has frequency of 1 Hz, and other 2 Hz, what does phase do to signal?

Actually Plot_ly plots have all data evaluated ahead of time, with the controls only determining what data gets called upon.

For a good example, look here: https://plotly.com/r/sliders/

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