00:01
All right, on this one, we're given y equals 7 plus 4 cosine of 3 times theta plus 10 degrees.
00:10
So the amplitude on this one is going to be 4.
00:16
The period, we have this 3, so we do 360 divided by 3.
00:22
We get 120, so our period is 120 degrees.
00:26
Phase displacement, we take this theta plus 10, set it equal to 0 .020.
00:31
So we have theta equals negative 10 degrees.
00:36
So that's our phase displacement.
00:38
Means we're going to move to the left by 10 degrees.
00:41
And then the sinusoidal axis, it starts at y equals 0.
00:45
And in this case, it is moving up by 7.
00:48
So it's going to be at y equals 7.
00:50
So now, if we plot our graph, so we know that we are going to be moving up by 7.
01:01
So whereas normally we would have gone up to four, now we're going to go up to 11, and then 7 is going to be our sinusoidal axis, and then our bottom point is going to be at 3, because negative 4 plus 7 is 3...