Question

Let the function f(x) have the form f(x) = Acos(x-C). To produce a graph that

matches the one shown below, what must the value of A be?

Answer 1

A has to be 2

Explanation:

In the expression
`f(x)=A*cos(x-C)`, the multiplicative factor A represents what is called the "amplitude of the wave-shaped function that you obtain as the graph. Such amplitude is understood as half of the crest-to-through distance of the wavy curve.

From the drawing, the crest is at y=2 and the through at y=-2 (a distance of 4 units) therefore the value of A should be half of that distance: 4/2 = 2