Logarithmic Problem: Is There an Error?

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The discussion highlights a mathematical error in applying logarithms to the expression a/b - a/b, which simplifies to zero. Since the logarithm of zero is undefined, the initial step of taking the logarithm leads to a breakdown in logic. The confusion arises from misinterpreting the equation -logb = log1, which should correctly imply 1/b = 1 rather than -b = 1. The key takeaway is that logarithmic functions can only be applied to positive values, making the original problem flawed. Understanding these principles is crucial to avoid contradictions in logarithmic equations.
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I an somewhat a layman, but i came across this problem. For any a & b, (b is not 0): ¤ a/b - a/b =0. [taking log to base 10 both sides] ¤ log(a/b - a/b) = log0. ¤ Log((a-a)/b) = log0. ¤Log(a-a) - logb = log0 ¤ log0 - logb = log0 ¤ -logb = log0-log0 ¤ -logb =0 ¤ -logb = log 1 [taking AL both sides] -b = 1. Can anyone point out the error here?There seems to be some inconsistancy.
 
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You should check to make sure you use actual carriage returns.

Anyways, your problem was right at the beginning -- the logarithm function is only defined for positive numbers. So, you cannot apply the logarithm function unless you can prove the two sides of the equation are positive.
 
First, log0 is not defined, so the entire logic falls apart there. This is about equivalent to dividing by zero, and we all know what contradictions that leads to...

Second, -logb = log1 implies 1/b = 1 not -b = 1.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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