
John M. answered 03/19/17
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- The quotient law of logs is Log(A/B) = Log A - Log B
- Let Log10 A = x. Then 10x = A {I'm using base 10, but any base could be used. I will not use the subscript any further}
- Similarly, let LogB = y. Then 10y = B
- Substituting: Log(A/B) = Log(10x/10y)
- We know from algebra that 10x/10y = 10x-y
- There is also the log property that says logaxn = n(logax)
- So Log(A/B) = Log(10x-y) = (x-y)(Log10)
- Log10 = 1, so we are left with (x-y) in the right side of equation
- And substituting for x-y yields LogA - LogB
- Log(A/B) - LogA - LogB