Hi Guys. I need your help.

In the attached file "amp.jpg" you will see a circuit. Suppose that R4/R3 =R2*(1−ε)/R1.

How to show that the differential mode gain and the common mode are those in the attached figure "re.jpg"?

Thank you so much in advance

 

Is this a homework problem? If so, it belongs in the homework help forum, and you would need to show some effort to solve it.

 

Hello,

There is a new thread started in the home work section:
Differential mode gain two amplifiers

Bertus