Hi everyone, I had a question about finding gain parameters. The question is part "c" in the attached "Gain Parameters Problem Picture.pdf" file. The correct answers to the problem are 18.86 [A/A] for Aisc and 9.428 [V/V] for Avo. My work for the problem is in the attached "Gain Parameters Problem Work Part 1.pdf" and "Gain Parameters Problem Work Part 2.pdf" files.
I don't understand why there is only one correct value for Aisc and one correct value for Avo in this problem, since there are two different values for "vi", the voltage across resistor "Riv". I used these two different values of "vi", which were "0.14 [V]" and "-0.14 [V]", to find two different values each, for Aisc and Avo. The values I got for Aisc were -18.86 [A/A] and 18.86 [A/A]. The values I got for Avo were -9.428 [V/V] and 9.428 [V/V]. I would appreciate any help in understanding why there is only one correct value for Aisc and Avo.