SOLUTION: If log (x+y)/2 = 1/2 (log x + log y) prove that x = y

Question 1119109: If log (x+y)/2 = 1/2 (log x + log y) prove that x = y
Answer by ikleyn(52776) (Show Source): You can put this solution on YOUR website!
.

If log (x+y)/2 = 1/2 (log x + log y), then


 =   ====>


x + y =     ====>  square both sides  ====>


 = 4xy


 = 0  ====>


 = 0  ====>   x = y.

Proved ans solved.

---------------------

Notice:   The given condition is equivalent to = ,

                and it is VERY WELL KNOWN FACT that the last equality is equivalent to x = y.

                My solution gives you the proof of this fact.

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