http://forum.allaboutcircuits.com – The book says that it is obvious that V0 is the negative of the ratio of the "feedback" resistor (8k ohms) to the input resistor (2k ohms) multiplied by the voltage the input terminal, thus it is -8 volts. It may be that my brain is currently fired, but the ratio of the resistors part through me for a loop. I was looking back trying to find the rule that allows that analysis to be done. I understand that the voltage at the node adjoining the 8 and 2 ohm resistors is 0. Before the 2 ohm resistor, the voltage is obviously 2 volts, and so the current flowing through both resis (Embedded)