Final answer:
The function that models the given simple harmonic motion is x(t) = 10 cos(2πt/3).
Step-by-step explanation:
To find a function that models the given simple harmonic motion with an amplitude of 10 cm and a period of 3 s, we can use the equation for displacement in SHM: x(t) = X cos(2πt/T). Plugging in the values for amplitude (X = 10 cm) and period (T = 3 s), the function becomes x(t) = 10 cos(2πt/3).