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PLEASE HELP....!!!!!! Need answer ASAP, so confused

PLEASE HELP....!!!!!! Need answer ASAP, so confused-example-1

1 Answer

2 votes

Answer:


b. \ y=3cos(3\theta)

Explanation:

The cosine function is a trigonometric function whose curve is symmetric with respect to the y-axis, hence this function is said to be even. This function has the following form:


y=acos(b \theta)

The amplitude of the plotted graph is 3 that represents half the distance between the maximum and minimum values. Since at x = 0, y = 3, this y-value is the value of a. On the other hand, the period, which is the length of one cycle of the curve, can be found as
T=(2\pi)/(3) and:


T=(2\pi)/(b) \therefore b=(2\pi)/(T)=(2\pi * 3)/(2\pi)=3

Finally:


\boxed{y=3cos(3\theta)}

User JPLemme
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