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    Using differentiation, find the turning points of the function y = x3 – 2x2 + 1 and sketch its curve.
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    (Original post by Deannnn97)
    Using differentiation, find the turning points of the function y = x3 – 2x2 + 1 and sketch its curve.
    What about it? Will I get paid if I do your homework for you? Show some attempt!
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    (Original post by Deannnn97)
    Using differentiation, find the turning points of the function y = x3 – 2x2 + 1 and sketch its curve.
    dy/dx = 3x2 - 4x
    = x(3x - 4)
    Turning points are (0,0) (1.33,0)
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    (Original post by Trapz99)
    dy/dx = 3x2 - 4x
    = x(3x - 4)
    Turning points are (0,0) (1.33,0)
    Thanks, so would this be a u shape or a n shape? I am not sure whether the shape comes from the +/-x or the +/- of the number?
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    (Original post by Trapz99)
    dy/dx = 3x2 - 4x

    = x(3x - 4)
    Turning points are (0,0) (1.33,0)
    You missed a step, you need to sub the x values back into y to find the y coordinates at the stationary point.


    (Original post by Deannnn97)
    Thanks, so would this be a u shape or a n shape? I am not sure whether the shape comes from the +/-x or the +/- of the number?
    Neither, it's a cubic curve.
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    Sorry I misread the question.

    When you draw the graph for x3 - 2x2 + 1 that's a cubic curve and not u or n shaped
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    (Original post by Trapz99)
    No I didn't miss anything.

    It's not a cubic curve. 3x2 - 4x doesn't have any cube
    That's \frac{dy}{dx}

    The curve is  y = x^3 - 2x^2 +1 written in the OP.
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    (Original post by Trapz99)
    Sorry I misread the question.

    When you draw the graph for x3 - 2x2 + 1 that's a cubic curve and not u or n shaped
    you need to sub your X values into the original equation for the stationary points, not the differential
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    The answer is:
    a) dy/dx = 3x2 - 4x
    0 = x (3x - 4)
    x = 1.33 x =0
    y = -5/27 y = 1
    So (1.33, -0.1852) and (0,1) are turning points
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    (Original post by Bananapeeler)
    you need to sub your X values into the original equation for the stationary points, not the differential
    Lol yeah I messed up
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    Do you understand why we have to use differentiation to be able to sketch the curve more accurately, or are you doing it for the sake of it?
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    (Original post by RDKGames)
    What about it? Will I get paid if I do your homework for you? Show some attempt!
    Homework at this time of year?
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    (Original post by ODES_PDES)
    Homework at this time of year?
    Perhaps the summer schools are stepping it up a notch.
 
 
 
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