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    So, I was just thinking to myself, you know, as you do: if a question states an equation has real roots does that mean the discriminant is
    b^2-4ac \geq 0 or does it mean b^2-4ac > 0

    It doesn't specify that it has equal / different real roots so it should be
    b^2-4ac \geq 0

    Right?
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    (Original post by Kozmo)
    So, I was just thinking to myself, you know, as you do: if a question states an equation has real roots does that mean the discriminant is
    b^2-4ac \geq 0 or does it mean b^2-4ac > 0

    It doesn't specify that it has equal / different real roots so it should be
    b^2-4ac \geq 0

    Right?
    If it doesn't specify distinct roots then when it says a quadratic has real roots then the discriminant is b^2 - 4ac \geq 0 since real and equal roots are still real roots.
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    (Original post by Kozmo)
    So, I was just thinking to myself, you know, as you do: if a question states an equation has real roots does that mean the discriminant is
    b^2-4ac \geq 0 or does it mean b^2-4ac > 0

    It doesn't specify that it has equal / different real roots so it should be
    b^2-4ac \geq 0
    b^2-4ac \geq 0 as if it is equal to zero it still has one root, which is still a real root
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    (Original post by Zacken)
    x
    :ninja:
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    Well yes, since equal roots would mean the discriminate is equal to zero.

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    (Original post by KaylaB)
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    :ninja:
    There was a whole two minute gap. :teehee:
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    (Original post by Zacken)
    There was a whole two minute gap. :teehee:
    I think you'll find it was a one minute gap :closedeyes:
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    and I had to edit my post multiple times because I accidentally deleted my reply when I quoted you :getmecoat:
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    (Original post by Zacken)
    If it doesn't specify distinct roots then when it says a quadratic has real roots then the discriminant is b^2 - 4ac \geq 0 since real and equal roots are still real roots.
    (Original post by KaylaB)
    b^2-4ac \geq 0 as if it is equal to zero it still has one root, which is still a real root
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    (Original post by sammyyrosee)
    Well yes, since equal roots would mean the discriminate is equal to zero.

    Yep, thought so, thanking you all!
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    (Original post by Kozmo)
    Yep, thought so, thanking you all!
    You're very welcome!
 
 
 
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