Math- logarithms

Why is (log3 400)/2 equivalent to log3 20? Can you show me how you can prove that step by step, without a calculator? Thank you so much!

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  1. is
    log 400 = 2 log 20 ??
    well
    log a^x = a log x
    so
    2 log 20 = log 20^2
    and lo and behold
    20^2 = 400

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    posted by Damon
  2. Oh, thank you so much! I did not think of making 400 20^2.

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