SOLUTION: Use the properties of exponents to prove the Power Property of Logarithms.

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Question 1039561: Use the properties of exponents to prove the Power Property of Logarithms.
Answer by Edwin McCravy(20064) About Me  (Show Source):
You can put this solution on YOUR website!
   
The power property of logarithms, which we 
are to prove, is

(1)   log%28B%2C%28A%5EC%29%29%22%22=%22%22C%2Alog%28B%2C%28A%29%29

But first we prove this: 

(2)   A+%22%22=%22%22+B%5Elog%28B%2CA%29  

-----------------

Let log%28B%2CA%29%22%22=%22%22x

Then by definition of logarithm

A+%22%22=%22%22+B%5Ex

Substitute for x

A+%22%22=%22%22+B%5Elog%28B%2CA%29

So we have proved (2).

-----------------

Let log%28B%2CA%5EC%29%22%22=%22%22y

Then by the definition of logarithm:

B%5Ey%22%22=%22%22A%5EC

Using (2) to replace A

B%5Ey%22%22=%22%22%28B%5Elog%28B%2CA%29%29%5EC

Use the rule of multiplying 
exponents on the right:

B%5Ey%22%22=%22%22B%5E%28C%2Alog%28B%2CA%29%29

Equate the powers of B

y%22%22=%22%22C%2Alog%28B%2CA%29

Since y%22%22=%22%22log%28B%2CA%5EC%29

log%28B%2CA%5EC%29%22%22=%22%22C%2Alog%28B%2CA%29

So we have proved (1)

Edwin