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Math Help - fractional indices

  1. #1
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    fractional indices

    how do you solve

    9^x = 27

    thanks for any feedback
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  2. #2
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    Quote 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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  3. #3
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    Quote 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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  4. #4
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    Thanks. That really helped.
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