P-2.18 Determine the values of the parameters {o, q,A} in the equations below. \text { (b) } 10 \cos (9 \mathrm{t}-\pi / 3)=\mathrm{A} \cos (\omega \mathrm{t}-\pi / 2)+5 \cos (\omega \mathrm{t}+\varphi)