Find equivalent resistance in this circuit

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Hyperfluxe
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Homework Statement


http://session.masteringengineering.com/problemAsset/1515645/4/Steif.ch02.p28.jpg
Find the equivalent resistance between node A and B, knowing that Rab = Vab/Iab

Homework Equations


KCL and KVL, I know.


The Attempt at a Solution


There is nothing in series or parallel here, so what I did is set up KCL equations and KVL loop equations (top and bottom loops), so 6 equations with 6 unknowns and I can find Iab. I don't know how to find Vab though...
 
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You don't find Vab, you stick a voltage source there (value of your choosing, or just leave it as a variable, "Vab"). The equivalent resistance Rab is given by the ratio Vab/Iab.

Presumably the Vab variable will cancel out in the workings leaving you with an expression for Rab in terms of R alone.
 
I'm still confused though, is my method of finding Iab correct?
 
Hyperfluxe said:
I'm still confused though, is my method of finding Iab correct?

Well, the approach of finding Iab given a source voltage Vab is correct. But you haven't shown the details of your work so it's not possible to say more.
 
Hyperfluxe said:
I'm still confused though, is my method of finding Iab correct?

You don't need to solve the equations to find Iab or Vab their own.

Rab = Vab/Iab

so reaarange the equations until you get one for the ratio Vab/Iab in terms of the resistors only.