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Homework Help: Simple Factoring Problems

  1. Sep 6, 2006 #1
    Hello, I am having a few minor factoring problems. Answers are not matching the answer book. I will show you what I have done


    =p^2 - 2p +1 - y^2 -2yz - z^2

    =(p-1)^2 (-y-z)(y+z)

    (the answer book states (p-1+y+z)(p-1-y-z))

    I dont know how the got that



    next

    x^2 +2 +(1/x^2)

    =x^4 + 2x^2 +1
    =(x^2+1)^2


    answer says (x+1/x)^2

    help please
     
  2. jcsd
  3. Sep 6, 2006 #2

    0rthodontist

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    If you want to be correct, always multiply it out or substitute something in to see if you're right or not.

    You already know how to factor the first three terms into a squared term involving p. Can you do something similar with the last three terms?

    Not true--plug in some values to check. However, what IS true, is
    x^2 +2 +(1/x^2) = (x^4 + 2x^2 +1)/(x^2)
     
  4. Sep 6, 2006 #3
    thanks for the help on the first one

    for the second one i got to

    [(x^2+1) (x^2+1)]/x^2

    how does that get to

    (x+1/x)^2
     
    Last edited: Sep 6, 2006
  5. Sep 6, 2006 #4

    0rthodontist

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    Science Advisor

    ((x^2+1)/x)^2
     
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