Question

Use the image to answer the question.

A waveform is plotted on a coordinate plane. The x-axis ranges from 0 to 2 pi in increments of pi. The y-axis ranges from negative 1 to 1 in unit increments.
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Write the equation of the trigonometric function that is represented in the graph.

(1 point)
f(x)=cos
(
)
Remaining Attempts : 3

Answer 1

I can't see the graph from your message. Could you either upload the image or type the key points from the graph (x-values where f(x)=1, f(x)=0, and f(x)=-1, or the x-coordinate(s) of a peak and the next peak)?

If you prefer to find it yourself, use this procedure:
- Determine the period p = distance between two consecutive identical points (e.g. consecutive peaks). Then b = 2π/p.
- Find any x0 where the cosine has a maximum of 1. If the maximum occurs at x = x0, the phase shift is x0 and the function is f(x) = cos[b(x − x0)]. If the graph has a maximum at x = 0, no phase shift is needed.
- If the graph is upside down (maximum at -1 where cos normally gives +1), include a minus sign: f(x) = −cos[b(x − x0)].

Give me one or two points from the graph (for example: maxima at x = π/4 and 9π/4, or zeros at x = π/2, 3π/2), and I will write the exact f(x) for you.