1. The problem statement, all variables and given/known data Beta=100,Thermal Voltage=0.026 Volts, Va=infinity, and Vbe=0.75 Volts for the differential amplifier. Please look at the upload for a clearer picture. 2. Relevant equations Ad=betaRc/2(rpi+Rb) Acm=-gmRc/(1+(2(1+beta)Ro/(rpi+Rb))) 3. The attempt at a solution I have uploaded my attempt but I am wondering if Ro is really zero I mean Va is infinity so I would think so but this would cause Acm=0 and CMRR= infinity this seems incorrect what am I doing wrong?