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    Attachment 608132Can I get help with this question I have no idea how to do it ?
    It shows a sketch of the graph y=f(x) where f(x)=x^3 - 6x^2 + 9x. The graph has a maximum at A and a Minimum at B (3 , 0).
    a) Find the co-ordinates of the turning point
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    (Original post by raquelmcg26)
    Can I get help with this question I have no idea how to do it ?
    It shows a sketch of the graph y=f(x) where f(x)=x^3 - 6x^2 + 9x. The graph has a maximum at A and a Minimum at B (3 , 0).
    a) Find the co-ordinates of the turning point
    can u not take a photo of the question?
    that would be helpful
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    (Original post by raquelmcg26)
    Can I get help with this question I have no idea how to do it ?
    It shows a sketch of the graph y=f(x) where f(x)=x^3 - 6x^2 + 9x. The graph has a maximum at A and a Minimum at B (3 , 0).
    a) Find the co-ordinates of the turning point
    Derivative of f(x) is equal to 0 at a turning point. Use this to form an equation and solve for x.
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    (Original post by CorpusLuteum)
    can u not take a photo of the question?
    that would be helpful
    I'm trying to attatch now
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    (Original post by SherlockHolmes)
    Derivative of f(x) is equal to 0 at a turning point. Use this to form an equation and solve for x.
    so you use stationary points ?
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    Differentiate f(x) and solve it. You'll end up with 2 values for x, of which one is 3 because the question tells you so. You can substitute the other value of x in to get your second set of coordinates for the other turning point.

    If you weren't told which is a maximum and minimum then find the second derivative and sub in the coordinates at the turning points, if it's positive then you have a minimum and vice versa.
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    I know maths I haeving a maths degree frum best colleg
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    (Original post by raquelmcg26)
    so you use stationary points ?
    Yes since a turning point is a type of stationary point.
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    (Original post by SherlockHolmes)
    Yes since a turning point is a type of stationary point.
    Okay Thank you
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    (Original post by Euler's Identity)
    I know maths I haeving a maths degree frum best colleg
    BTEC in maths doesn't count bhai
    Even if Btec is frm Oxbridge or Camford :sad:
    I shud kno. Maths Btec only allow me 2 become supermarket sweeper
 
 
 
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