SOLUTION: I need to know the amplitude and period of y=4cos(3.14x)+4 If a graph can be shown that would be helpful as well

Algebra ->  Trigonometry-basics -> SOLUTION: I need to know the amplitude and period of y=4cos(3.14x)+4 If a graph can be shown that would be helpful as well      Log On


   

Question 588281: I need to know the amplitude and period of y=4cos(3.14x)+4
If a graph can be shown that would be helpful as well
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Amplitude:

In general, the amplitude of y+=+Acos%28Bx-C%29%2BD is abs%28A%29

In your case, A=4. So abs%28A%29=abs%284%29=4. So the amplitude of y=4cos%283.14x%29%2B4 is 4.

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Going back to the general equation y+=+Acos%28Bx-C%29%2BD, the period is T=%282pi%29%2FB

In the equation y=4cos%283.14x%29%2B4, the value of B is B=3.14. So the period is T=%282pi%29%2FB+=+%282pi%29%2F%283.14%29+=+2.00101442903809

So the period is approximately 2.00101442903809

Note: this value is close to 2 because 3.14 is close to pi. If you really meant pi instead of 3.14, then the period would truly be 2.

A graph of y=4cos%283.14x%29%2B4 is shown below