Answer:
amplitude = 3
Step-by-step explanation:
The standard form of a cosine function is
f(x) = a cos(bx + c) + d
amplitude = | a |, period = [tex]\frac{2\pi }{b}[/tex]
phase shift = - [tex]\frac{c}{b}[/tex], d is the vertical shift
Given the above function, then
amplitude = | - 3 | = 3