If the input impedance is defined as $\mathbf{Z}_{\mathrm{in}}=\mathbf{V}_{s} / \mathbf{I}_{s}$ find the input impedance of the op amp circuit in Fig. 10.96 when $R_{1}=10 \mathrm{k} \Omega, R_{2}=20 \mathrm{k} \Omega$
$C_{1}=10 \mathrm{nF}, C_{2}=20 \mathrm{nF},$ and $\omega=5000 \mathrm{rad} / \mathrm{s}$