Question: A disaster response team models the periodic power grid stability using the function $ p(t) = 9\cos\left(\frac\pi12t\right) + 12\sin\left(\frac\pi12t\right) $. What is the amplitude and the phase shift $ \phi $ in the equivalent form $ R\cos\left(\frac\pi12t - \phi\right) $? - Appfinity Technologies