Question

Use the image to answer the question.

A waveform is graphed on a coordinate plane, and five points are plotted along it. The x-axis ranges from negative pi to 3 pi in increments of Start Fraction pi over 2 End Fraction. The y-axis ranges from negative 4 to 2 in increments of 1.
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What is the midline of the cosine function?

(1 point)
Responses

d=−158

d equals negative Start Fraction 15 over 8 End Fraction

d=18

d equals Start Fraction 1 over 8 End Fraction

d=−78

d equals negative Start Fraction 7 over 8 End Fraction

d=π

d equals pi

Answer 1

d = 1/8

(The midline = (max + min)/2; from the graph max = 1 and min = −3/4, so (1 + (−3/4))/2 = 1/8.)