SOLUTION: Simplify. (u^4)^-7 Write your answer without using negative exponents.

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Question 273074: Simplify.
(u^4)^-7
Write your answer without using negative exponents.
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Simplify.
(u^4)^-7
---
u^-28
---
(1/u)^28
=================
Cheers,
Stan H.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The general rules for powers raised to powers are:
(1) %28a%5Eb%29%5Ec+=+a%5E%28b%2Ac%29
(2) %28a%5E%28-b%29%29%5Ec+=+a%5E%28-b%2Ac%29
(3) %28a%5Eb%29%5E%28-c%29+=+a%5E%28b%2A%28-c%29%29
(4) %28a%5E%28-b%29%29%5E%28-c%29+=+a%5E%28%28-b%29%2A%28-c%29%29
The other rules you need are
(5) 1%2F%28a%5Eb%29+=+a%5E%28-b%29
(6) 1%2F%28a%5E%28-b%29%29+=+a%5Eb
Notice that (1) and (4) give the same result, and
(2) and (3) give the same result
-------------------------
%28u%5E4%29%5E%28-7%29+=+1%2F%28u%5E4%29%5E7 (this is just rule (5) backwards)

%28u%5E4%29%5E%28-7%29+=+1%2Fu%5E%284%2B4%2B4%2B4%2B4%2B4%2B4%29
%28u%5E4%29%5E%28-7%29+=+1%2Fu%5E28
%28u%5E4%29%5E%28-7%29+=+u%5E%28-28%29
This is just rule (3)