SOLUTION: Express this as a single logarithm: 1) log(x2-4)- 2 log(x+2) ( the first 2 is squared)

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Question 126233: Express this as a single logarithm:
1) log(x2-4)- 2 log(x+2)
( the first 2 is squared)
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The general rules are log%28a%29+-+log%28b%29+=+log%28a%2Fb%29
and a%2Alog%28b%29+=+log%28b%5Ea%29
You can prove this by picking some number for a, say
a+=+7, then
7%2Alog%28b%29+=+log%28b%2Ab%2Ab%2Ab%2Ab%2Ab%2Ab%29

7%2Alog%28b%29+=+7%2Alog%28b%29
---------------------------
log%28%28x%5E2+-+4%29%29+-+2%2Alog%28%28x+%2B+2%29%29
log%28%28x%5E2+-+4%29%29+-+log%28%28x+%2B+2%29%5E2%29
log%28%28x%5E2+-+4%29+%2F+%28x+%2B+2%29%5E2%29
log%28%28%28x+-+2%29%28x+%2B+2%29%29+%2F+%28%28x+%2B+2%29%28x+%2B+2%29%29%29
log%28%28x+-+2%29+%2F+%28x+%2B+2%29%29 answer