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?

A. 2
B. 3
C. 4
D. 1

Please explain. Thank you!

Answer 1

the amplitude of cos wave goes from
\(\Large - A \to A\)
on y axis

Answer 2

now can you figure out Amplitude = A = ... ?