Distributing negative signs in logarithms

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SUMMARY

The correct simplification of the logarithmic expression ##\log(A \times B \div C \times D)## is ##\log(A) + \log(B) - \log(C) + \log(D)##. This conclusion is based on the standard convention that the expression should be interpreted as ##\log[\frac{AB}{CD}]##. The discussion highlights the importance of clear notation, emphasizing that the use of the division sign (##\div##) is outdated in algebraic contexts, where fractions are preferred for clarity.

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Homework Statement
Simplify ##\log(A \times B \div C \times D)##
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Simplify ##\log(A \times B \div C \times D)##

Is it ##\log(A)+\log(B)-(\log(C)+\log(D))## or ##\log(A)+\log(B)-\log(C)+\log(D)##?

I'm leaning toward the former but not sure. Thanks.
 
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It depends on whether the statement means
##log[\frac {ab} {cd}]## or ##log[\frac {abd} {c}]##
Normal convention says the latter so log(a)+log(b)-log(c)+log(d)
 
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RChristenk said:
Simplify ##\log(A \times B \div C \times D)##
I have not seen any algebra textbooks that would show problems like this. As already noted, the expression in parentheses should be written as either ##\frac{AB}C \cdot D## or as ##\frac{AB}{CD}##. Failing that, there should at least be parentheses around CD to emphasize that this is the divisor.
Is this a problem from some textbook? If so, my guess is that it is substandard or very old.
Also, algebra textbooks generally don't use the ##\div## sign.
 

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