SOLUTION: ln(y-6)=ln(y+6)+ln4

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Question 40982: ln(y-6)=ln(y+6)+ln4
Found 2 solutions by psbhowmick, stanbon:
Answer by psbhowmick(878) About Me  (Show Source):
You can put this solution on YOUR website!
ln(y-6) = ln(y+6) + ln4
or ln(y-6) - ln(y+6) = ln4
or ln%28%28y-6%29%2F%28y%2B6%29%29+=+ln4
Therefore %28y-6%29%2F%28y%2B6%29+=+4
or [by componendo and dividendo]
or -2y%2F12+=+5%2F3
or y = -10


This is impossible because then (y+6) and (y-6) become negative and logarithm of negative number is undefined. I think you have copied the problem wrongly. Instead of what you have written the question should be ln(y-6) = ln(y+6) - ln4. Then y = 10.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
ln(y-6)=ln(y+6)+ln4
ln(y-6)=ln4(y+6)
Take the anti-ln of both sides to get:
y-6=4y+24
-3y=30
y=-10
This is a meaninless answer because there
is no ln of negative numbers which is what
you would have if you substituted this value
into the original equation.
Conclusion: No solution
cheers,
Stan H.