For an equation like (12.2.1) which has real coefficients, if exp(iωt) is a solution, then so is exp(−iωt), so the superposition of these two solutions is a...For an equation like (12.2.1) which has real coefficients, if exp(iωt) is a solution, then so is exp(−iωt), so the superposition of these two solutions is also a solution. The quantity ω≡(ω20−β2)1/2 is the actual frequency of oscillation of the damped oscillator, which one can see is less than the oscillation frequency ω 0 that occurs with the damping turned off.