(a) Using Eqs. (30.21) and (30.23) for an L-C circuit, write expressions fur the energy stored in the capacitor as a function of time and for the enetgy stored in the inductor as a function of time.
(b) Using Eq. (30.22) and the trigonometric identity sin2 x + cos2 x = 1, show !hat the total energy in the Ire circuit is constant and equal to Q2/2C.