Find the voltage gain of the classical difference amplifier

[lgrada14]

Find the voltage gain of the classical difference amplifier for the case R1 = R3 = 10 kΩ and R2 = R4 =
100 kΩ. What is the differential input resistance Rid? If the two key resistance ratios and are different from
each other by 1%, what do you expect the common-mode gain Acm to be? Also, find the CMRR in this case.
(a) Neglect the effect of the ratio mismatch on the value of Ad and (b) do not neglect the mismatch.

[pebe]

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