Question

Find the input resistance Rab=_______Ω.

Answer 1

find input resistance Rab=...........ohm

Answer 2

Might be a much easier way of doing this, but the I get Rab = 3 ohms by doing a lot of Wye-delta transforms. http://en.wikipedia.org/wiki/Wye-delta_transform

You can also apply an arbitrary voltage, find the current using mesh analysis, and then V/I = R. I get 3ohms using this method as well.

Let me know if you find an easier way, I'm pretty curious. These methods all seem like overkill.