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Homework Help: Help pls

  1. Nov 5, 2008 #1
    hi all

    I need some help with this question

    Let (a,b)=1 and ab=c^2. Show that a and b are perfect squares.

    Thank you
  2. jcsd
  3. Nov 5, 2008 #2


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    Science Advisor
    Homework Helper

    Look at the prime factorization of a, b and c.
  4. Nov 5, 2008 #3


    Staff: Mentor

    It took me a little while to comprehend what you meant by (a, b) = 1, but I concluded that you mean that a and b are relatively prime, namely that the largest factor they both share is 1.

    To get you thinking about this the right way, try a few examples by assigning different values to a and b to see how that affects their products. The values you choose for a and b should be relatively prime. Keep in mind that your examples won't constitute a proof; they just help you think about the problem, and might help you formulate a real proof.
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