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    I was doing a Core 3 Past Paper (AQA, June 2014) but wasn't entirely sure about how many marks I would get for some questions:

    On question 2)a, it says dy/dx = -2 x (1/(2e-x))

    I put dy/dx = -2 / 2e-x. Is this full marks?

    Likewise for question 3)a:

    The markscheme says 5/2 x 2x(x^2+1)^3/2

    I put 5x(x^2+1)^3/2

    For 3)b, the question says to find the x coordinates of the stationary points. I found them correctly, but I also found the y coordinates. Do I drop a mark for this?

    For question 4)c)i, the markscheme says the stretch is scale factor 1/2 // x axis

    Is stretch, scale factor 1/2 in the x direction the right thing?

    For 6)a, the markscheme puts the constant of integration as a capital C

    I put mine as a lower case c. Do I drop the final mark?

    Thanks for all your help
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    (Original post by MathsALevel123)
    I was doing a Core 3 Past Paper (AQA, June 2014) but wasn't entirely sure about how many marks I would get for some questions:

    On question 2)a, it says dy/dx = -2 x (1/(2e-x))

    I put dy/dx = -2 / 2e-x. Is this full marks?
    Assuming the -2 x (...) is multiplication, you would get full marks.

    (Original post by MathsALevel123)
    Likewise for question 3)a:

    The markscheme says 5/2 x 2x(x^2+1)^3/2

    I put 5x(x^2+1)^3/2
    Assuming 5/2 x 2 x (x^2+1)^(3/2) (bolded is multiplication) then yes, full marks.[/quote]
    (Original post by MathsALevel123)
    For 3)b, the question says to find the x coordinates of the stationary points. I found them correctly, but I also found the y coordinates. Do I drop a mark for this?
    No. Full marks.

    (Original post by MathsALevel123)
    For question 4)c)i, the markscheme says the stretch is scale factor 1/2 // x axis

    Is stretch, scale factor 1/2 in the x direction the right thing?
    You may lose a mark here, x direction is a bit ambigous, I would stick with stretch parallel to the x axis, that's what the // means parallel.

    (Original post by MathsALevel123)

    For 6)a, the markscheme puts the constant of integration as a capital C

    I put mine as a lower case c. Do I drop the final mark?
    No.
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    (Original post by Zacken)
    Assuming the -2 x (...) is multiplication, you would get full marks.



    Assuming 5/2 x 2 x (x^2+1)^(3/2) (bolded is multiplication) then yes, full marks.
    It is 5/2 times 2x (x^2+1)^3/2 and I put 5x(x^2+1)^3/2

    No. Full marks.



    You may lose a mark here, x direction is a bit ambigous, I would stick with stretch parallel to the x axis, that's what the // means parallel.

    Oh. I always used to do parallel to the x axis but then I changed it for some reason...

    What's the difference between the 2?


    No.[/QUOTE]
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    (Original post by MathsALevel123)
    It is 5/2 times 2x (x^2+1)^3/2 and I put 5x(x^2+1)^3/2

    No. Full marks.



    You may lose a mark here, x direction is a bit ambigous, I would stick with stretch parallel to the x axis, that's what the // means parallel.

    Oh. I always used to do parallel to the x axis but then I changed it for some reason...

    What's the difference between the 2?


    No.
    [/QUOTE]

    Well, you could mean a stretch perpendicular to the x-axis, you need to state that it's parallel.

    Also, yes, your 5/2 thing is correct.
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    Well, you could mean a stretch perpendicular to the x-axis, you need to state that it's parallel.

    Also, yes, your 5/2 thing is correct.[/QUOTE]

    Ok. Thanks for all your help
 
 
 
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