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  #1  
Old October 6th, 2009, 12:33 PM
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Default fractional indices

how do you solve

9^x = 27

thanks for any feedback
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  #2  
Old October 6th, 2009, 12:45 PM
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Originally Posted by charmifs View Post
how do you solve

9^x = 27

thanks for any feedback
I would suggest that you take a logarithm of both sides.

Remember that \log_a (a^b) = b

So proceed like so:

\log_9 (9^x) = \log_9 (27)
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Old October 6th, 2009, 12:49 PM
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Originally Posted by charmifs View Post
how do you solve

9^x = 27

thanks for any feedback
Another way is to use the powers of 3:

(3^2)^x = 3^{2x} =  3^3

If the bases are equal so too must the exponents:

2x = 3
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Old October 7th, 2009, 01:08 PM
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Thanks. That really helped.
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