How to Solve This Logarithmic Problem?

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Multiply both sides by 2, 2*log((x-y)/3)=log(x)+log(y). Now what? Show us what you try.
 
log((x - y)/3) = 1/2(log x + log y)
==> log((x - y)/3) = 1/2(log xy)
==> log((x - y)/3) = log (xy)1/2

Now, if the logs of two numbers are equal, then the two numbers must be equal. (Equivalently you could exponentiate each side of the equation; that is, make each side the exponent on 10. 10log a = a as long as a > 0.
 
Thank-you so much.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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