SOLUTION: Evaluate log 4 base 1/2

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Question 974641: Evaluate log 4 base 1/2
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Evaluate log 4 base 1/2
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log%280.5%2C4%29
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You can always use the base change formula:
log%28b%2Ca%29+=+log%28a%29%2Flog%28b%29
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log%280.5%2C4%29+=+log%284%29%2Flog%281%2F2%29
= -2
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You might recognize that 1%2F2+=+2%5E-1
and 4+=+2%5E2
--> %282%5E%28-1%29%29%5Ex+=+2%5E2
2%5E%28-x%29+=+2%5E2
x = -2