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    ok i've been revising + this paper just shockd me

    http://www.xtremepapers.net/OCR/Math.../Paper%201.pdf

    question 9) i) how are you mean't to differenatiate it?
    i have no idea how u re-arrange that equation and differentiate it

    and 10) c) why on earth does x-7(3x+22)+14 make x = -7??

    please help

    x
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    (Original post by Sparkzz)
    ok i've been revising + this paper just shockd me

    http://www.xtremepapers.net/OCR/Math.../Paper%201.pdf

    question 9) i) how are you mean't to differenatiate it?
    i have no idea how u re-arrange that equation and differentiate it

    and 10) c) why on earth does x-7(3x+22)+14 make x = -7??

    please help

    x
    what paper is this?
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    (Original post by sohail.s)
    what paper is this?
    soloman paper A
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    (Original post by Sparkzz)
    ok i've been revising + this paper just shockd me

    http://www.xtremepapers.net/OCR/Math.../Paper%201.pdf

    question 9) i) how are you mean't to differenatiate it?
    i have no idea how u re-arrange that equation and differentiate it

    and 10) c) why on earth does x-7(3x+22)+14 make x = -7??

    please help

    x
    it rearranges to: 0.5x - x^-1 + 3
    can you go from there?
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    (Original post by jim666666)
    it rearranges to: 0.5x - x^-1 + 3
    can you go from there?
    yes yes thank u

    and any ideas about 10) ii) ??
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    (Original post by Sparkzz)
    ok i've been revising + this paper just shockd me

    http://www.xtremepapers.net/OCR/Math.../Paper%201.pdf

    question 9) i) how are you mean't to differenatiate it?
    i have no idea how u re-arrange that equation and differentiate it

    and 10) c) why on earth does x-7(3x+22)+14 make x = -7??

    please help

    x
    For the first differentiation question, treat \frac{x}{2} as \frac{1}{2}x and -\frac{1}{x} as -x^{-1}. You should be able to differentiate it following the usual rules.
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    (Original post by asparkyn)
    For the first differentiation question, treat \frac{x}{2} as \frac{1}{2}x and -\frac{1}{x} as -x^{-1}. You should be able to differentiate it following the usual rules.

    thanks + any ideas about 10) ii) for finding C?
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    (Original post by Sparkzz)
    thanks + any ideas about 10) ii) for finding C?
    Well, I ran through it quickly, and I got x = 7 instead of x = -7. Where did you get that figure from? As far as I know x - 7(3x + 22) + 14 = 0 seems pretty correct.
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    (Original post by Sparkzz)
    yes yes thank u

    and any ideas about 10) ii) ??
    to find b set x to 0

    to find c set the equations of the two lines equalto eachother and solve
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    Simultaneous equations with the two line equations.

    Do you notice on the front page of the papers how it says that

    "These sheets may be copied for use solely by the purchaser’s institute"?

    Do you think that xtremepapers have paid Solomon Press or Shaun Armstrong for the use of these papers?
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    (Original post by asparkyn)
    Well, I ran through it quickly, and I got x = 7 instead of x = -7. Where did you get that figure from? As far as I know x - 7(3x + 22) + 14 = 0 seems pretty correct.
    how does x-7(3x+22)+14 =0 make x=7?
    dont u expand the brackets out and get x-21x+154+14??
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    (Original post by Sparkzz)
    how does x-7(3x+22)+14 =0 make x=7?
    dont u expand the brackets out and get x-21x+154+14??

    Yes you do expand the brackets - check your expansion again btw.

    x=7 is one of the answers - there are two.
 
 
 
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