Final answer:
The equation of a sine function with an amplitude of 2 and a period of 4π is y = 2sin(x).
Step-by-step explanation:
The equation of a sine function with an amplitude of 2 and a period of 4π is y = 2sin(x) (option c).
The general equation of a sine function is y = A sin(Bx + C), where A is the amplitude, B determines the period, and C represents any phase shift.
In this case, the amplitude is 2, so A = 2. The period is 4π, so B = 2π/4π = 1/2. There is no phase shift, so C = 0.
Substituting the values into the general equation, we get y = 2sin(x).