Question 308702: log base 2 (3x+4)- log base 2 (x)= 1
do I turn this into a fraction?
Found 2 solutions by texttutoring, rapaljer:
Answer by texttutoring(324)   (Show Source):
You can put this solution on YOUR website! Use one of the logarithm laws. If you're subtracting a log of the same base, you can just turn it into a fraction with the same log base. I'll show you what I mean:
log base 2 (3x+4/x) = 1
Next, you need to use the definition of log, log base b (x) = y, where x=b^y.
Use this to convert to:
(3x+4)/x = 2^1
(3x+4)/x = 2
3x+4 = 2x
x+4=0
x=-4
Answer by rapaljer(4671)  (Show Source):
You can put this solution on YOUR website! Yes indeed!!!
By the law of logarithms:
By definition of logarithms,
Multiply both sides by x:
This answer is not allowed, since it causes there to be a log of a negative. There is NO SOLUTION!!
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Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus
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