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C1 question

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    Can't believe I'm stuck on this question but yh, need help :l

    kx^2 +12x + k =0

    k = +ve

    and it has equal roots

    ^ I know this means that both values of x are the same but I have no idea how to do it!
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    (Original post by 0range)
    Can't believe I'm stuck on this question but yh, need help :l

    kx^2 +12x + k =0

    k = +ve

    and it has equal roots

    ^ I know this means that both values of x are the same but I have no idea how to do it!
    Hint b^2 - 4ac = 0
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    B^2-4ac =

    144-4k^2=0

    k^2=36

    k=6

    6x^2+12x+6=0

    x^2+2x+1=0

    (x+1)^2=0
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    (Original post by zincoff)
    B^2-4ac =

    144-4k^2=0

    k^2=36

    k=6

    6x^2+12x+6=0

    x^2+2x+1=0

    (x+1)^2=0
    Please don't post full solutions.

    First give hints to the OP, post full solutions as a last resort.
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    (Original post by steve2005)
    Hint b^2 - 4ac = 0
    Missed that! Thanks!

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