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    question 10 on the c1 paper from may 13th, was a bit of a srange one, and I got completely stuck and confused but I kept getting the same answer to part (i) (k=-5) every single way I to work out it out, I was just wondering how anyone else would work it out and if they got the same answer as me

    y=(1-x)(X^2-2x+k) and the information given was that there is a stationary point at x=-3. (I can't quite remember if that was the formula of the line but that's what I think it was)
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    Was this AQA?

    Regardless, there's no point panicking about it because there is absolutely nothing you can do about it now. Just forget about it, do well on the rest of your exams, and await results.
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    It was OCR, I'm actually hoping to god that I at least put down -5 even if it was the wrong answer to earn back some marks!
    It's really kicked my butt into gear about revising hard good luck for any you're sitting!
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    k=-5 is the right answer.
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    That's just put my mind so at rest
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    I believe theres an unofficial mark scheme that explains all the answers.

    K = -5 is the correct answer.

    I did it in two ways, if you were curious:

    First, you find dy/dx and sub x as -3, which leaves you with k = -5
    Alternatively you can use the quadratic formula, equating it to -3. This leaves you with something like 18 = 6 + root[84-12k) so since the square root must equal 12, 84-12k = 144, thus 12k = -60 k = -5.

    I'm sure theres also other methods, but these worked for me.
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    yeah I did it in the exam through differentiating, but I confused myself by plugging -5 back into the equation and when I did that then the equation didn't work and now I can't remember if I put down an answer! Thanks for your help guys!
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    (Original post by jazzyjay29)
    question 10 on the c1 paper from may 13th, was a bit of a srange one, and I got completely stuck and confused but I kept getting the same answer to part (i) (k=-5) every single way I to work out it out, I was just wondering how anyone else would work it out and if they got the same answer as me

    y=(1-x)(X^2-2x+k) and the information given was that there is a stationary point at x=-3. (I can't quite remember if that was the formula of the line but that's what I think it was)
    http://www.thestudentroom.co.uk/show....php?t=2350074
 
 
 
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