Voltage in a Circuit: Calculate with Current Divider

[-EquinoX-]

Homework Statement

http://img696.imageshack.us/img696/7609/circuit.jpg

Homework Equations

The Attempt at a Solution

I know that the answer of the question below is D, but how do I get to that answer?

My guess would be to use current divider to find the current going through v0 then we can calculate v0 then divide by is.

When I do that I got a very complicated result...

My calculations for the current divider is to find the equivalent resistance in the circuit, which is:

R1R2/R1+R2 || R1R2/R1+R2
which is R1R2/2R1+2R2

Then after calculating the v0/is I got R1R2/2(R1+R2). This doesn't seem to match the answers above
is this approach correct so far?

 

[rl.bhat]

Vo/Is is the resistance. It does not depend on the branch current. The current in the circuit is Is. Vo is the same for R1 and R2.
So what is Vo across that branch? Convert the equivalent resistance into G to get the required answer.

 

[-EquinoX-]

Vo/Is is the resistance. It does not depend on the branch current. The current in the circuit is Is. Vo is the same for R1 and R2.
So what is Vo across that branch? Convert the equivalent resistance into G to get the required answer.

the equivalent resistance is this:

R1R2/2R1+2R2

 

[rl.bhat]

the equivalent resistance is this:

R1R2/2R1+2R2

From where did you get 2?
The resistance of desired branch is \frac{1}{G_{}1+G_{}2}