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    I drew up a little diagram in photoshop of the question I'm stuck on..

    http://jdesign.org/question.jpg

    I think I've done it right so far, but I've written the question down just in case.

    I need to know how to find the area (idk if this is even the right place to ask but I am desperate )
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    Find where curve algebra = 0

    x^2 - 3x = 0
    x(x - 3) = 0
    so x = 0 or 3


    You've drawn the area wrong... the curve passes through (0,0) surely?

    If so:

    Area of Triangle - Integral between 0 and 1 of (x^2 - 3x)
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    put the 2 lines equal to each other and rearrange...integrate that equation for the area of the sail..
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    (Original post by Mat666)
    Find where curve algebra = 0

    x^2 - 3x = 0
    x(x - 3) = 0
    so x = 0 or 3


    You've drawn the area wrong... the curve passes through (0,0) surely?

    If so:

    Area of Triangle - Integral between 0 and 1 of (x^2 - 3x)

    Yeah, the curve passes through (0, 0) I drew it wrong lol.

    I'm really new to all this stuff, so I don't really know what you're talking about Some school wants me to take a test to get in, and this was a q on last years paper :/
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    (i) y = 3x - x²
    y' = 3 - 2x
    =======

    (ii)B(1,2)
    at x = 1, y' = 3 - 2 = 1
    y' = 1
    ====
    Tangent to y at B has gradient m = 1

    y - y1 = m(x - x1)
    y - 2 = 1.(x - 1)
    y - 2 = x - 1
    y = x + 1
    ======

    (iii)
    The tangent cuts the x-axis at y = 0
    =>x = -1
    =====
    Therefore A is (0, -1)
    ===============

    (iv)
    Area of sail is area of triangle with AB as its hypotenuse minus the area under the curve y = 3x - x² from x = 0 to x = 1.
    Area of triangle = A1 = ½.2.2 = 2
    A1 = 2 sq units
    ==========

    A2 = ∫ {0 -> 1} 3x - x² dx
    A2 = [3x²/2 - x³/3]{0 -> 1}
    A2 = 3/2 - 1/3
    A2 = 7/6
    ======

    A = A1 - A2
    A = 2 - 7/6
    A = 5/6
    =====
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    (Original post by hughy)
    I drew up a little diagram in photoshop of the question I'm stuck on..

    http://jdesign.org/question.jpg

    I think I've done it right so far, but I've written the question down just in case.

    I need to know how to find the area (idk if this is even the right place to ask but I am desperate )
    Are you doing the additional maths FSMQ paper, I'm doing it at the moment aswell, I didn't think I would meet anyone who knew what it was!
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    (Original post by hughy)
    Yeah, the curve passes through (0, 0) I drew it wrong lol.

    I'm really new to all this stuff, so I don't really know what you're talking about Some school wants me to take a test to get in, and this was a q on last years paper :/
    have you worked through the textbook for add.maths, is it being taught to you at school, because this stuff you really need to be taught how to do.
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    (Original post by Louise_1988)
    have you worked through the textbook for add.maths, is it being taught to you at school, because this stuff you really need to be taught how to do.
    Heh, I just moved to the UK from Canada, and I don't really know much of anything in the additional mathematics paper. I'm just sort of going through last years paper and trying to teach myself whatever is covered in it.
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    Fermat thx for the help. You explained it well

    Also thanks to everyone else
 
 
 
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