Answer:
Option (4)
Step-by-step explanation:
From the graph attached,
Equation of the wave function is a cosine function.
Let the graphed function is, f(x) = -Acos(bx - ∅)
Amplitude of the given function,
A = [tex]\frac{4-(-4)}{2}[/tex] = 4 units
Period = [tex]\frac{2\pi }{b}[/tex] = 2π
b = [tex]\frac{2\pi }{2\pi }[/tex] = 1
Given graph is starting from (0, 0).
Therefore, from the given graph, Phase shift of the cosine curve = ∅ = [tex]\frac{\pi }{2}[/tex]
Therefore, equation of the given cosine function will be,
f(x) = -4cos(x - [tex]\frac{\pi }{2}[/tex])
Option (4) will be the answer.