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View Full Version : text(ln)(x+3) - text(ln)(2x) = (text(ln)(x+3))/(text(ln)(2x))


bd1177
Apr 25, 2012, 09:52 AM
Is the above formatted equation true or false when dealing with logarithms.

ebaines
Apr 25, 2012, 09:58 AM
It appears what you're trying to ask is whether this is true:


ln(x+3) - ln(2x) = \frac {ln(x+3)}{ln(2x)}


No these are not equaivalent. But the following IS true:


ln(x+3) - ln(2x) = ln (\frac {x+3}{2x} )


The principals to remember are: ln(a x b ) = ln(a) + ln(b), and ln(a/b) = ln(a) - ln(b).