SOLUTION: If a^2+b^2=7ab prove that 2 log(a-b)=log 5+log a+log b

Question 1043490: If a^2+b^2=7ab prove that 2 log(a-b)=log 5+log a+log b
Answer by ikleyn(52813) (Show Source): You can put this solution on YOUR website!
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If a^2 + b^2=7 ab, then prove that 2 log (a-b)=log 5+log a+log b
~~~~~~~~~~~~~~~~~~~~

If  = , then

 =     (after adding 2ab to both side)

 = .

Now take the logarithm of both sides (assuming a > b > 0, which MUST be pointed in the condition, but mistakenly missed).
You will get

2*log(a-b) = log(5) + log(a) + log(b).   QED.

Solved.

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