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Homework Help: Factoring question

  1. Sep 11, 2011 #1
    1. The problem statement, all variables and given/known data
    Factor
    X^6+8


    2. Relevant equations
    The answer: (x^2 + 2)(x^4 - 2x^2 + 4)


    3. The attempt at a solution
    I'm really not sure how to arrive at the answer. Although, I have a feeling that I have to use (a + b)(a^2 - ab + b^2) because the question looks looks similar to a^3 + b^3
     
  2. jcsd
  3. Sep 11, 2011 #2

    Dick

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    You've already got it. If a^3+b^3=x^6+8, what should a and b be?
     
  4. Sep 11, 2011 #3
    I suppose this is where I'm stuck.

    a= x^2
    b= 2

    ?
    I'm still a bit confused on how we got a = x^2
     
  5. Sep 11, 2011 #4

    Dick

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    You want a^3 to equal x^6, right? You don't see why (x^2)^3=x^6?
     
  6. Sep 11, 2011 #5
    I see it now.
    Thank you :)
     
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