Question 46500: Please show me how to evaluate this without using a calculator?
log5 20 . log20 60. log60 100 . log100 125.
Thanks! Answer by joyofmath(189) (Show Source):
You can put this solution on YOUR website! Please show me how to evaluate this without using a calculator?
log5 20 . log20 60. log60 100 . log100 125.
Thanks!
In general, log[a]b * log[b]c = log[a]c
So, log[5]20 * log[20]60 = log[5]60
Then, log[5]60 * log[60]100 = log[5]100
And, log[5]100 * log[100]125 = log[5]125
Finally, log[5]125 is the number you have to raise 5 to in order to get 125. That number is .
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