SOLUTION: how would i solve 81 with a negative 3/4 power

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Question 401530: how would i solve 81 with a negative 3/4 power
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Make use of the general formulas:
a%5E%28-b%29+=+1%2F%28a%5Eb%29
%28a%5Eb%29%5Ec+=+a%5E%28b%2Ac%29
given:
81%5E%28-3%2F4%29+=+1%2F%2881%5E%283%2F4%29%29
Now note that 81+=+3%5E4
Replace 81 with this expression
1%2F%28%283%5E4%29%5E%283%2F4%29%29
This equals
1%2F3%5E%28%284%2F4%29%2A3%29
This equals
1%2F%283%5E3%29
1%2F27 answer