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Hi, I am having trouble filling out the nodal equation for the node of the first op-amp towards the left. Let's say that node voltage is Vx. (V-)

I know that, Vx - 5 / 70k + ~~~~ = 0... I don't know what to put for the ~~~~ part. I know the current has to equal the current across teh 70kohm resistor because the current into an ideal op amp is equal to 0. I'm a bit confused as to HOW to model the current leaving that node to the particular branch.

If you can't figure out what I'm talking about, it's toward the left part of the 60k and 30k resistor... that node.

http://img172.imageshack.us/img172/3728/screenshot01sd4.jpg [Broken]

I also want to verify that there is another node by the + polarity of the V0. That node will have voltage V0. So, the KCL equation for that node will be:

V0 / 30k + (V0 - Vx) / 60k = 0, right?

I know that, Vx - 5 / 70k + ~~~~ = 0... I don't know what to put for the ~~~~ part. I know the current has to equal the current across teh 70kohm resistor because the current into an ideal op amp is equal to 0. I'm a bit confused as to HOW to model the current leaving that node to the particular branch.

If you can't figure out what I'm talking about, it's toward the left part of the 60k and 30k resistor... that node.

http://img172.imageshack.us/img172/3728/screenshot01sd4.jpg [Broken]

I also want to verify that there is another node by the + polarity of the V0. That node will have voltage V0. So, the KCL equation for that node will be:

V0 / 30k + (V0 - Vx) / 60k = 0, right?

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