# Homework Help: Solving an equation

1. Jul 29, 2009

### physucsc11

1. The problem statement, all variables and given/known data
To solve the following equation for x in terms of R and 3 constants a,b, and c:

R = ((a^-x)-(b^-x))/((c^-x)-(a^-x))

2. Relevant equations

Just the given equation

3. The attempt at a solution

I have tried taking the natural log of both sides but that doesn't seem to get me anywhere. Any suggestions?

2. Jul 29, 2009

### Staff: Mentor

Your equation can be rewritten as
$$R = \frac{1/a^x - 1/b^x}{1/c^x - 1/a^x}$$

I would start with combining the two expressions in the numerator and the two in the denominator and simplify, then see where that takes me.