How do you use the amplitude and period to graph $y=5+8cos2x$ ?

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Answer 1 · 2016-04-22T08:16:28

This cosine wave has mean level along y = 5.

The period of y = b+a cos( kx + c) is $(2pi)/k$ .
The amplitude is a and the mean level is y = b.

Here, b = 2, a = 8 and k = 2. So, the period is $pi$ .

The graph of one full wave is between $(-pi/4, 5) and ((3 pi)/4, 5)$ , bisected at $(pi/4, 2)$ .

The crest (zenith) is at (0. 13) and the lowest point (nadir) is at $(pi/.2, -3)$ .. .

How do you use the amplitude and period to graph y=5+8cos2xy=5+8cos2x?