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    Why is y= 3x (2x-1) (2x + 1)

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    and not like this:

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    (Original post by JodieW)
    Why is y= 3x (2x-1) (2x + 1)

    drawn like this:

    Name:  ImageUploadedByStudent Room1365091795.824944.jpg
Views: 43
Size:  26.8 KB

    and not like this:

    Name:  ImageUploadedByStudent Room1365091857.343732.jpg
Views: 47
Size:  27.1 KB


    Posted from TSR Mobile
    They are not the same graph.
    Its cubic, it has 3 real roots at x=0, 1/2 and -1/2
    It will be a positive cubic so will enter from the 3rd quadrant and exit from the first.
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    (Original post by m4ths/maths247)
    They are not the same graph.
    Its cubic, it has 3 real roots at x=0, 1/2 and -1/2
    It will be a positive cubic so will enter from the 3rd quadrant and exit from the first.
    So was the second graph correct? The book says it is the first graph, and I'm confused.


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    (Original post by JodieW)
    So was the second graph correct? The book says it is the first graph, and I'm confused.


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    You can check this for yourself.
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    (Original post by JodieW)
    So was the second graph correct? The book says it is the first graph, and I'm confused.


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    Graph
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    (Original post by JodieW)
    So was the second graph correct? The book says it is the first graph, and I'm confused.


    Posted from TSR Mobile
    You would need a negative x^3 term to have the graph that enters from the 2nd Q and leaves in the 4th Q
 
 
 
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