www.piclist.com/techref/index.htm?key=formula+unbalanced

Any maths wizards out there....?

Given a conventional resistance bridge :

Vin

+----+

R1 R2

+----|--- Vout (differential)

| +---

R3 Rx

+----+

GND

What is the formula to determine Rx (Or, better, the ratio Rx/R3)

given the ratio Vout/Vin. R1=R2 if that makes anything easier.

My algebra isn't quite up to juggling it round - I got as far as the

following before my brain started to hurt :

Rx/(Rx+R2) = V-(R3/(R1+R3)

where V is the ratio Vout/Vin

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