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Math Help - Real Roots

  1. #1
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    Smile Real Roots

    Hi! I've tried to solve this question, but I came to the conclusion that I couldn't so I gave up! I hope you can help me with this one

    The equation x^2 - 2kx + 1 = 0 has two distinct real roots. Find the set of all possible values of k.

    I would appreciate your help

    Thanks,
    Amine.
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  2. #2
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    Hi

    The discriminant is \Delta = (-2k)^2-4 = 4(k^2-1)

    The equation x^2 - 2kx + 1 = 0 has two distinct real roots if \Delta > 0

    Can you go on ?
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  3. #3
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    Does the final answer give 1/2(x + 1/x)?
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  4. #4
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    Quote Originally Posted by Aminekhadir View Post
    Does the final answer give 1/2(x + 1/x)?
    Not really
    Don't forget you are asked to find a set of values of k
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  5. #5
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    Ok, I will try to figure it out
    Thanks for the help!
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