You have to write a equation

y = 3 sin 4x

Step-by-step explanation:

For y = a sin bx,

a is the amplitude which is the crest of the graph. In this case a = 3 from the given graph.

Now, b is associated with the period where; b = 2π/period

From the graph the period which is the time between where the graph crosses the x-axis = π/2

Thus; b = 2π/(π/2)

b = 4

Thus,equation is; y = 3 sin 4x

answer:

c. the third graph

21/58.

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