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    I have been given a curve y= 3 + 5x + x2 - x3

    I need to find the co ordinates of point A and B and show they are maximum and minimum.

    dy/dx = 3x2 - 2x + 5

    I should then factorise which I can't do so should use the quadratic formula?

    -(-2) +/- sqrt 22 - (4) (3) (5)
    ______________________
    2 * 3

    I get a math error on the calculator. Any help?
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    it should say

    dy/dx = -3x2 + 2x + 5

    ====> 3x2 - 2x - 5 = 0

    etc
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    (Original post by the bear)
    it should say

    dy/dx = -3x2 + 2x + 5

    ====> 3x2 - 2x - 5 = 0

    etc
    Thank you so much! Amazing how a simple mistake can cause so much aggro
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    (Original post by ak992)
    Thank you so much! Amazing how a simple mistake can cause so much aggro
    :console:

    hey we have all been there

 
 
 
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