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    Given the roots of the equation kx (squared) - 6x +3k=0. Find the value of k where k >0

    I know you use the discriminant but i'm not sure what sign to use etc can anyone help please
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    (Original post by Misshussain23)
    Given the roots of the equation kx (squared) - 6x +3k=0. Find the value of k where k >0

    I know you use the discriminant but i'm not sure what sign to use etc can anyone help please
    Just use the discriminant and solve it, simple! And when it comes to the sign if its a negative then it will change.
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    Use the discriminant. Remember the sign always changes to the opposite when multiplying it with a negative value.
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    (Original post by Misshussain23)
    Given the roots of the equation kx (squared) - 6x +3k=0. Find the value of k where k >0

    I know you use the discriminant but i'm not sure what sign to use etc can anyone help please
    Are you sure thats the correct question?
    I've tried it myself and got this:

    kx(squared) - 6x + 3k = 0
    b(squared) - 4ac > 0

    (-6)(squared) - 4 x k x 3k
    36 -12k(squared) > 0
    36 > 12k(squared)
    3 > k(squared) ( Divided 36 by 12 )

    But yea now I'm confused what to do if k>0 then it must have 2 solutions so wtf
    Actually I think I did it right .. you then
    do the square root of both sides to give:

    3(root sign) > k or k< 3(root sign)

    I think thats it
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    The question seems to be incomplete. It mentions roots but doesn't say what they are, whether they're equal, distinct etc.
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    (Original post by SeanFM)
    The question seems to be incomplete. It mentions roots but doesn't say what they are, whether they're equal, distinct etc.
    If it says k>0 I'm sure it will be "real roots"
    Don't you think so?
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    (Original post by RoadtoSuccess)
    If it says k>0 I'm sure it will be "real roots"
    Don't you think so?
    k is a constant used in the equation rather than the discriminant.
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    (Original post by SeanFM)
    k is a constant used in the equation rather than the discriminant.
    I know but what if thats what he meant you could be right I'm having doubts with my working out but who knows could be that dodgy question ^_-
 
 
 
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