SOLUTION: log base 9 cubed root of 3

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Question 634999: log base 9 cubed root of 3
Found 2 solutions by jsmallt9, MathTherapy:
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
log%289%2C+%28root%283%2C+3%29%29%29
This expression represents "the power of 9 that results in +root%283%2C+3%29". If you're very good with exponents, then you you can figure this our in your head.

If not, then the key to figuring this out is to recognize that both 9 and +root%283%2C+3%29 are both powers of 3: 9+=+3%5E2 and root%283%2C+3%29+=+3%5E%28%281%2F3%29%29. Once we realize this, then we would know that converting the base of the logarithm to 3 will make this problem easier.

The base conversion formula is log%28a%2C+%28p%29%29+=+log%28b%2C+%28p%29%29%2Flog%28b%2C+%28a%29%29. We can use this to convert our base 9 log to an expression of base 3 logs:
log%283%2C+%28root%283%2C+3%29%29%29%2Flog%283%2C+%289%29%29
The numerator represents "the power of 3 that results in +root%283%2C+3%29. We know that this is 1/3. And the denominator represents "the power of 3 that results in 9". This is known to be 2. Substituting these into our expression we get:
%281%2F3%29%2F2
which simplifies (by multiplying the top and bottom of the "big" fraction by 3) to:
+1%2F6

P.S. Perhaps now you can look back and see how you could have figured this out "the power of 9 that results in +root%283%2C+3%29" in your head. The power of 9 that results in 3 is 1/2 since 3 is the square root of 9. So we want the exponent for the cube root of the square root of 9:

Answer by MathTherapy(10557) About Me  (Show Source):
You can put this solution on YOUR website!

log base 9 cubed root of 3

log_%5B9%5D%28root%283%2C3%29%29 ----- log_%5B9%5D%283%5E%281%2F3%29%29 ----- %281%2F3%29+%2A+log_%5B9%5D%283%29 ----- %281%2F3%29%28%28log+3%29%2Flog%289%29%29 ----- %281%2F3%29%280.5%29 ----- highlight_green%280.167%29

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