Question 171164: solve the logarithymatic equation. Express irratiional solitions in simplist radical form.
log(x+1)-log(x+5)=log1/x Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! solve the logarithymatic equation. Express irratiional solitions in simplist radical form.
log(x+1)-log(x+5)=log(1/x)
log(x+1) = log(1/x)+log(x+5)
log(x+1) = log[(1/x)(x+5)]
Take the anti-log to get:
(1/x)(x+5) = x+1
1 + (5/x) = x+1
Multiply thru by x to get:
x + 5 = x^2 + x
x^2=5
x = sqrt(5) or x = -sqrt(5)
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-sqrt(5) is extraneous as it would make log(x+1) be the log of a negative #.
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Ans: x = sqrt(5)
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Cheers,
Stan H.
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