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Moonspex
Apr17-10, 12:39 PM
I've been trying to derive this expression but all I come up with is flimsy reasoning via Ohm's Law. Could anyone suggest a way of deriving it?

rbe / ß+1 = re

All I can see is that, since

ib = ie / ß+1

and in Ohm's Law, r & i are inversely proportional, then the first expression should be true. However, then there is the problem that in the first expression, it is rbe, not rb which makes me doubt my assumption.