Which of the following functions illustrates a change in amplitude?

Hey there! :)

C.

Step-by-step explanation:

For a graph to have a change in amplitude, there must be a coefficient in front of the equation, or the 'a' value.

Recall that the transformation form of a trigonometric graph is:

y = ±a(cos(b(x-h))+k

Where 'a' is the amplitude

'b' changes the period

'h' is a horizontal shift

'k' is a vertical shift

We can look at each choice and eliminate:

A. There is only a coefficient of -1 in front of the equation, which simply results in a reflection over the x-axis. This is incorrect.

B. This equation contains a b value of 2. This changes the period of the graph, not the amplitude. This is incorrect.

C. This equation contains a coefficient, or 'a' value of -2. The amplitude is changed by a factor of 2. This is correct.

D. This graph only contains a vertical shift of 1 unit up. This is incorrect.

Therefore, C is the correct answer.

i believe the answer is letter c) 8

step-by-step explanation:

- both graphs increase on their domain.

- the graphs of both functions have the same x-intercept.

- neither graph has a y-intercept.