9.34 The analysis of the high-frequency response of the common-
source amplifier, presented in the text, is based on the
assumption that the resistance of the signal source, Rsig, is large
and, thus, that its interaction with the input capacitance Cin produces
the “dominant pole” that determines the upper 3-dB frequency
fH. In some situations, however, the CS amplifier is fed
with a very low Rsig. To investigate the high-frequency response
of the amplifier in such a case, Fig. P9.34 shows the equivalent
circuit when the CS amplifier is fed with an ideal voltage
source Vsig having Rsig = 0. Note that CL denotes the total capacitance
at the output node. By writing a node equation at the output,
show that the transfer function Vo/Vsig is given by