Hi, I had a question about finding current gain. The question is part "ii" in the attached "Problem Picture.pdf" file. The correct answer for the question is: infinity. My work for the problem is shown in the attached "Work for Problem.pdf" file.

I don't understand how the answer of infinity makes sense, because, if io is nonzero, then io/iin should be undefined, and if io is zero, then io/iin should be indeterminate, since iin is always zero.

Would anyone have an idea as to why the correct answer is infinity for the current gain, io/iin?

I don't understand how the answer of infinity makes sense, because, if io is nonzero, then io/iin should be undefined, and if io is zero, then io/iin should be indeterminate, since iin is always zero.

Would anyone have an idea as to why the correct answer is infinity for the current gain, io/iin?