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    Please can someone help

    the question is Solve the following inequality

    X^2 -7x +12<0

    if you factorise it you get (x-3)(x-4)
    so the answeer would be 3,4<0 but this isn't correct someone please help
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    You could take numbers either side of those numbers and put it into the x^2-7x+12 and see if it comes out as above or below zero, numbers plus/minus 0.1 from the answers you found above,

    x = 3.1 y=-0.09
    x = 2.9 y= 0.11

    x= 4.1 y=0.11
    x= 3.9 y = -0.09
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    (Original post by Meat Loaf Rocks)
    Please can someone help

    the question is Solve the following inequality

    X^2 -7x +12<0

    if you factorise it you get (x-3)(x-4)
    so the answeer would be 3,4<0 but this isn't correct someone please help
    (x-3)(x-4)<0
    One of the brackets has to be negative at the same time as the other is positive.
    (x-3) can't be negative while (x-4) is positive.
    Hence (x-4) is negative and (x-3) is positive.
    so: 3<x<4.
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    cheers great help
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    The way I do it is by sketching the graph, for easier examples anyway like quadratics. It will be below the x axis when x<0, so you can see that it must be between 3 and 4, but not including 3 and 4 because at those points y=0, so it isn't <0.

    x > 3 and x < 4 so

    3 < x < 4
 
 
 
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