Sketch one cycle of the cosine function. y = 2 cos 2 theta

So the question ask to sketch the one cycle of the cosine function where as the y = 2cos theta. So base on the function, its just and ordinary graph but the data is not the same. The line begins at the positive 2 in the Y axis then goes down with constant magnitude after it reach its limit it goes up again with constant magnitude and its limit in negative y axis is - 2.