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    part b)

    I know what to do but I'm having a nightmare rearranging to find a nice equation for the normal as such in the mark scheme.

    here's my working so far
    Attached Images
     
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    (Original post by BTAnonymous)
    http://www.physicsandmathstutor.com/...papers/c3-aqa/

    June 2016 q 4. b)

    I know what to do but I'm having a nightmare rearranging to find a nice equation for the normal as such in the mark scheme.
    Move to the Maths study help forum.
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    (Original post by BTAnonymous)
    bump
    The thread has literally been here 40 mins, have a bit of patience.
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    (Original post by 04MR17)
    The thread has literally been here 40 mins, have a bit of patience.
    Then you can deduce that i'm an extremely impatient person.
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    (Original post by BTAnonymous)
    Then you can deduce that i'm an extremely impatient person.
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    (Original post by 04MR17)
    So long since I last heard this!
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    BTAnonymous, would you like to show your working so far?
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    (Original post by 04MR17)
    BTAnonymous, would you like to show your working so far?
    can't embed it onto my original post for some reason.


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    Which exam board is this?
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    (Original post by BTAnonymous)
    can't embed it onto my original post for some reason.


    Paste this in.

    [img]https://i.imgur.com/zw0pOlQ.jpg[/img]
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    (Original post by VictiniCup)
    Which exam board is this?
    aqa old spec
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    (Original post by BTAnonymous)



    part b)

    I know what to do but I'm having a nightmare rearranging to find a nice equation for the normal as such in the mark scheme.

    here's my working so far
    I can't follow what you've done.

    find dy/dx. Plug in the x value at p for the gradient of the tangent.

    Flip and times by -1 for the gradient of the normal.

    use y-y1=m(x-x1) to find the equation of the normal.

    Plug in the zeroes to find where it crosses the axes.

    use 1/2bh to find the area of the triangle.
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    (Original post by NotNotBatman)
    I can't follow what you've done.

    find dy/dx. Plug in the x value at p for the gradient of the tangent.

    Flip and times by -1 for the gradient of the normal.

    use y-y1=m(x-x1) to find the equation of the normal.

    Plug in the zeroes to find where it crosses the axes.

    use 1/2bh to find the area of the triangle.
    was missing this. ty
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    (Original post by NotNotBatman)
    I can't follow what you've done.

    find dy/dx. Plug in the x value at p for the gradient of the tangent.

    Flip and times by -1 for the gradient of the normal.

    use y-y1=m(x-x1) to find the equation of the normal.

    Plug in the zeroes to find where it crosses the axes.

    use 1/2bh to find the area of the triangle.
    oh im an idiot. I forgot to plug in the x value for my gradient of the normal. smh.
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    (Original post by BTAnonymous)
    oh im an idiot. I forgot to plug in the x value for my gradient of the normal. smh.
    Did you manage to get the answer?
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    (Original post by NotNotBatman)
    Did you manage to get the answer?
    almost, however it looks like I have mine in a different form but is still numerically the same.

    my form:

     2e^{-1} + e + e^{-3}

    mark scheme:

     \frac{(e^2 + 1)^{2}}{e^{3}}
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    (Original post by BTAnonymous)
    almost, however it looks like I have mine in a different form but is still numerically the same.

    my form:

     2e^{-1} + e + e^{-3}

    mark scheme:

     \frac{(e^2 + 1)^{2}}{e^{3}}
    If the answer they are looking for is a single fraction, then you should probably write your answer as a single fraction.

    Yes your answer is the same as the mark scheme, but you need to be able to convert to it otherwise you don't get the last mark.
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    (Original post by BTAnonymous)
    almost, however it looks like I have mine in a different form but is still numerically the same.

    my form:

     2e^{-1} + e + e^{-3}

    mark scheme:

     \frac{(e^2 + 1)^{2}}{e^{3}}
    e^(-n) =1/(e^n)

    Use this and turn it into a single fraction using the LCM.
 
 
 
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