SOLUTION: If log{{x+y}/3}=1/2{logx+log Y}, then find the value of x/y+y/x?

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Question 977752: If log{{x+y}/3}=1/2{logx+log Y}, then find the value of x/y+y/x?
Found 2 solutions by rothauserc, MathTherapy:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
log{{x+y}/3}=1/2{logx+log Y}
log(x+y) - log(3) = 1/2(log xy)
log(xy) - log(2) = 1/2(log xy)
2xy - 4 = xy
xy = 4
now
x/y + y/x =
(x^2 + y^2) / xy =
(x^2 + y^2) / 4
we have two cases
(4, 1) and (2,2) are factors of 4
1) (16 + 1) / 4 = 17/4
2) (4 + 4) / 4 = 2

Answer by MathTherapy(10704) About Me  (Show Source):
You can put this solution on YOUR website!
If log{{x+y}/3}=1/2{logx+log Y}, then find the value of x/y+y/x?
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What the other person who responded did and said, doesn't make any sense, at all, to this author. Plus, nowhere in his response,
is there an answer to the question: What's the value of x%2Fy+%2B+y%2Fx?

             log+%28%28%28x+%2B+y%29%2F3%29%29+=+%281%2F2%29+log+%28%28x%29%29+%2B+log+%28%28y%29%29
        log+%28%28x+%2B+y%29%29+-+log+%28%283%29%29+=+%281%2F2%29+log+%28%28xy%29%29
    2+log+%28x+%2B+y%29+-+2+log+%283%29+=+log+%28%28xy%29%29 ---- Multiplying by 2
     log+%28%28x+%2B+y%29%29%5E2+-+log+%28%283%29%29%5E2+=+log+%28%28xy%29%29
      log+%28%28x+%2B+y%29%29%5E2+-+log+%28%289%29%29+=+log+%28%28xy%29%29
     log+%28%28x+%2B+y%29%29%5E2+-+log+%28%28xy%29%29+=+log+%28%289%29%29
             log+%28%28x+%2B+y%29%5E2%2Fxy%29+=+log+%28%289%29%29 
                %28x+%2B+y%29%5E2%2Fxy+=+9 ---- Applying c = d, if log+%28b%2C+%28c%29%29+=+log+%28b%2C+%28d%29%29
         %28x%5E2++%2B+2xy+%2B+y%5E2%29%2Fxy+=+9 ---- FOILing %28x+%2B+y%29%5E2
           x%5E2%2Fxy+%2B+2xy%2Fxy+%2B+y%5E2%2Fxy+=+9 ---- Dividing each expression on left-side by xy

               x%2Fy+%2B+2+%2B+y%2Fx+=+9 
                 x%2Fy+%2B+y%2Fx+=+9+-+2
                highlight%28x%2Fy+%2B+y%2Fx%29+=+highlight%287%29