SOLUTION: How would you apply a factoring formula to completely factor the expression "x4 - 1"?

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Question 34745: How would you apply a factoring formula to completely factor the expression "x4 - 1"?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Can you see this expression as the difference of two squares?
x%5E4+-+1+=+%28x%5E2%29%5E2+-+%281%29%5E2
The difference of two squares is factorable thus:
a%5E2+-+b%5E2+=+%28a+%2B+b%29%28a+-+b%29 Apply this to your problem.
%28x%5E2%29%5E2+-+%281%29%5E2+=+%28x%5E2+%2B+1%29%28x%5E2+-+1%29 Notice that the second parentheses is again the difference of two squares and can be factored as before.
%28x%5E2+-+1%29+=+%28x+%2B+1%29%28x+-+1%29
Putting it all together, we have:
x%5E4+-+1+=+%28x%5E2+%2B+1%29%28x+%2B+1%29%28x+-+1%29