SOLUTION: I need to evaluate log 0.001 without a calculator, but how?

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Question 606413: I need to evaluate log 0.001 without a calculator, but how?
Found 2 solutions by richard1234, Earlsdon:
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!


since log and exponentiation are inverse functions.

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Evaluate:
Log%5B10%5D%280.001%29 First, rewrite 0.001 as 10%5E%28-3%29
Log%5B10%5D%2810%5E%28-3%29%29 Now apply the "power rule" for logarithms: Log%5Bb%5D%28M%5En%29+=+n%2ALog%5Bb%5D%28M%29 to get:
-3Log%5B10%5D%2810%29 then substitute Log%5B10%5D%2810%29+=+1
-3%2A1+=+-3 so...
Log%5B10%5D%280.001%29+=+-3