# Electrical – Ideal Op-Amp circuit Output voltage expression

operational-amplifier

simulate this circuit – Schematic created using CircuitLab

Here I am trying to find or derive expressions for both Vo1 and Vo2 in terms of Vi1 and Vi2.
This is how I approach this. All resistors are the same. So I see that I can do KVL following I1 since there's no currents flowing into op amps.
So -Vi1 + I1xR + I1xR + Vo2 = 0 and this yields:
Vo2 = Vi1 – I1x(2R)

Vo1:
Because of virtual ground I concluded that Vi2 is seen mid-point between the two Rs at the output of op-amps. Consequently Vo1 = Vi2 – (I/2)xR.

Are my expressions for both Vo1 and Vo2 correct?

#### Best Answer

YOu should be able to figure of Vo2, given only what you know about op-amps, feedback, and the currents. Think about what the voltage must be on the positive input of the top op amp. Once you have that, you have I1. Once you have I1, you have Vo2.

That should give you your current through both feedback resistors, which will lead you to Vo1