GRAPHICAL REASONING

Question

Find a and d for the function f (x) = a cos x + d such that the graph of f  matche the figure.

Answer 1

Step 1:

The graph of the function is in the form of ,

where is amplitude and  is the shift along -axis.

Observe the graph.

The difference between the maximum height and the minimum height is twice of the amplitude of the function.

The amplitude of the function is .

Step 2:

Shift along -axis is  the average of the two heights.

.

Shift along -axis is .

Substitute the values and in the function .

.

Solution:

The function is .