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    I haven't ventured to the bottom to have a look at the mark scheme (because that doesn't normally help at all), but i'm so confused about what i'm supposed to do part 1 and how i'm supposed to do it. I realise it's probably fairly straight forward, but i just can't get my head around it.


    Thanks in advance
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    Post the question, for those of us without integral logins.
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    (Original post by CharleyChester)
    http://integralmaths.org/resources/f...apers/C4-A.pdf Question 5.


    I haven't ventured to the bottom to have a look at the mark scheme (because that doesn't normally help at all), but i'm so confused about what i'm supposed to do part 1 and how i'm supposed to do it. I realise it's probably fairly straight forward, but i just can't get my head around it.


    Thanks in advance
    Would you be able to copy out the question? I can't see it as you need to login to integral maths
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    (Original post by TimmonaPortella)
    Post the question, for those of us without integral logins.

    (Original post by jameswhughes)
    Would you be able to copy out the question? I can't see it as you need to login to integral maths
    Sorry! I forgot about the log-in thing. I screen captured the picture and put the link in the original post.
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    \frac{dx}{dt}=2at
    \frac{dy}{dt}=2a
    \frac{dy}{dx}=\frac{1}{t}

    For tangent
    y=mx+c
    where
    m= \frac{dy}{dx}

    Use y=2ap and x = ap^2 as given, and t=p so \frac{dy}{dx}=\frac{1}{p}

    so 2ap=ap+c therefore c=ap

    You now have a line, y= \frac{x}{p} + ap
    and to find where it crosses the x axis, y=0
    so x =-ap^2

    T=-ap^2

    I'll do N later, go to go now!
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    (Original post by CharleyChester)



    I haven't ventured to the bottom to have a look at the mark scheme (because that doesn't normally help at all), but i'm so confused about what i'm supposed to do part 1 and how i'm supposed to do it. I realise it's probably fairly straight forward, but i just can't get my head around it.


    Thanks in advance
    If the question was just

    "A point P on the curve f(x) = (equation) has coordinates (x,y).
    i) Find the coordinates of the point where the tangent meets the x-axis,
    ii) Find the coordinates of the point where the normal meets the x-axis"

    would you know how to go about it? It's the same method, but with parametric coordinates instead of cartesian. You should know how to find the gradient of a curve defined parametrically.
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    For the normal, repeat what I did earlier, with m=- (\frac{dx}{dy}) because the normal is perpendicular to the tangent, so the gradient is the negative inverse.
 
 
 
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