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red and white kop!
01-03-2012, 10:52 AM
Write down the period of the graph of y=3/(2+(cos2x)^2), and also the coordinates of a maximum value of y.

For the second question I answered correctly.
For the first, however I didnt.
It seems obvious to me that the period is 90, due to x being multiplied by 2 and the expression being squared; however the answer is 180.
Its also clear by the graph that the period is 90; is this a typo?

Subhotosh Khan
01-03-2012, 12:52 PM
Write down the period of the graph of y=3/(2+(cos2x)^2), and also the coordinates of a maximum value of y.

For the second question I answered correctly.
For the first, however I didnt.
It seems obvious to me that the period is 90, due to x being multiplied by 2 and the expression being squared; however the answer is 180.
Its also clear by the graph that the period is 90; is this a typo?

You are correct - the period of the given function is 90° or π/2.

red and white kop!
01-04-2012, 01:54 AM
thanks