Question 950304:  what is the equation in logarithmic form for 16=(1/4)-2? 
 
 Answer by Theo(13342)      (Show Source): 
You can  put this solution on YOUR website! i believe you mean 16 = (1/4)^(-2)
 
 
if you use your calculator to evaluate this equation, you will see that:
 
 
16 = 16.
 
 
this confirms the equation is true.
 
 
the ^ symbol indicates exponentiation.
 
 
the equation is 16 = (1/4)^-2
 
 
this is in the form of y = b^x, where:
 
 
y = 16 
b = (1/4) 
x = -2
 
 
in general, y = b^x if and only if log(b,y) = x
 
 
log(b,y) means log of y to the base of b.
 
 
apply that to your problem and you get:
 
 
16 = (1/4)^-2 if and only if log(1/4,16) = -2
 
 
how do you confirm?
 
 
use your calculator and the log conversion formula that tells you that:
 
 
log(1/4,16) = log(16) / log(1/4).
 
 
remember that log without mention of the base means the base is 10.
 
 
log(16) / log(1/4) means log of 16 to the base of 10 divided by log of 1/4 to the base of 10.
 
 
log to the base of 10 is the LOG function in your calculator.
 
 
your equation becomes:
 
 
log(16) / log(1/4) = -2
 
 
use your calculator to get:
 
 
-2 = -2
 
 
this confirms the conversion is correct.
 
 
 
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