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+// Example 10.20: (a) Low 3 dB frequency
+//                (b) High 3 dB frequency
+clc, clear
+// From Fig. 10.76
+C_gd1=2e-12; // in farads
+C_gs1=5e-12; // in farads
+gm1=10e-3; // in mho
+C1=1e-6; // in farads
+C_gd2=2e-12; // in farads
+C_gs2=5e-12; // in farads
+gm2=10e-3; // in mho
+C2=10e-6; // in farads
+// From low-frequency equivalent cicuit in Fig. 10.77
+RS=0.2e3; // in ohms
+RG1=50e3; // in ohms
+RS1=0.25e3; // in ohms
+RS2=0.15e3; // in ohms
+RD2=5e3; // in ohms
+R=10e3; // in ohms
+C3=5.3e-6; // in farads
+
+function[c]=parallel(a,b)
+    c=a*b/(a+b);
+endfunction
+
+disp("Part (a)");
+// From low-frequency equivalent cicuit in Fig. 10.77
+tau1=C1*(RS+RG1); // in seconds
+R_22=RD2+R; // in ohms
+tau2=C2*R_22; // in seconds
+R_33=parallel(RS2,1/gm2); // in ohms
+tau3=C3*R_33; // in ohms
+fL=(1/tau1+1/tau2+1/tau3)/(2*%pi); // in hertz
+disp(fL,"Low 3 dB frequency (Hz) =");
+
+disp("Part (b)");
+// From high frequency equivalent cicuit in Fig. 10.78
+R_gd1=parallel(RS,RG1); // in ohms
+// From Fig. 10.79
+R_gs1=(R_gd1+RS1)/(1+gm1*RS1); // in ohms
+R_gs2=parallel(RS1,1/gm2); // in ohms
+R_gd2=R_gs2+parallel(RD2,R)+R_gs2*parallel(RD2,R)*gm2; // in ohms
+a1=C_gd1*R_gd1+C_gs1*R_gs1+C_gs2*R_gs2+C_gd2*R_gd2; // in seconds
+fH=1/(2*%pi*a1); // in hertz
+fH=fH*1e-6; // in Mega-hertz
+disp(fH,"High 3 dB frequency (MHz) =");
+\ No newline at end of file