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    I think this is a simple question, I know what to do, but don't actually know why.
    In a question, where for example you differentiate a function to get dy/dx as 3x-4sqrtx - why is it when x is 4 (for example), do you only consider the positive root rather than the negative root, and will get 4 as your gradient, rather than 11. Just want to know why...


    Also, if I have the transformation of -3f(3x-2)+3, what order do I do the translations?

    Finally, is there on one proof i need to know for C1 (sum of n)?

    Thanks for ANY help!!!!!!!!
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    (Original post by IAmConfused1)
    I think this is a simple question, I know what to do, but don't actually know why.
    In a question, where for example you differentiate a function to get dy/dx as 3x-4sqrtx - why is it when x is 4 (for example), do you only consider the positive root rather than the negative root, and will get 4 as your gradient, rather than 11. Just want to know why...
    If you learnt that \sqrt{4} = \pm 2, that is categorically untrue and wrong. \sqrt{4} = + 2 always. Read this: http://www.thestudentroom.co.uk/show...5#post64637655

    Also - yes, you need only know the arithmetic sum to n proof.
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    (Original post by Zacken)
    If you learnt that \sqrt{4} = \pm 2, that is categorically untrue and wrong. \sqrt{4} = + 2 always. Read this: http://www.thestudentroom.co.uk/show...5#post64637655

    Also - yes, you need only know the arithmetic sum to n proof.
    Thanks so much, sorry to bother, but is there anyway you could try to explain the order of transformation for the problem I gave? (-3f(3x-2)+3?Thanks a lot
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    (Original post by IAmConfused1)
    Thanks so much, sorry to bother, but is there anyway you could try to explain the order of transformation for the problem I gave? (-3f(3x-2)+3?Thanks a lot
    You've given a fairly complex transformation there.

    I would change around the f(x) --> f(x - 2/3) (translate horizontally) then scale horizontally f(3x -2) --> -3f(3x-2) (scale veritcally) ---> -3f(x3-2) +3 (translate vertically)
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    (Original post by Zacken)
    You've given a fairly complex transformation there.

    I would change around the f(x) --> f(x - 2/3) (translate horizontally) then scale horizontally f(3x -2) --> -3f(3x-2) (scale veritcally) ---> -3f(x3-2) +3 (translate vertically)
    Lol do you think they'll give something that complex? wtf...
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    (Original post by Zacken)
    You've given a fairly complex transformation there.

    I would change around the f(x) --> f(x - 2/3) (translate horizontally) then scale horizontally f(3x -2) --> -3f(3x-2) (scale veritcally) ---> -3f(x3-2) +3 (translate vertically)
    Right, think I have got it, thanks
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    (Original post by TheProKi)
    Lol do you think they'll give something that complex? wtf...
    (Original post by IAmConfused1)
    Right, think I have got it, thanks
    They wouldn't, no.
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    Sorry to jack the thread, but...

    How do you do Q2 on JAN 11 C1 OCR?

    http://www.ocr.org.uk/Images/65379-q...hematics-1.pdf
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    (Original post by Zacken)
    They wouldn't, no.
    I've just done C1 specimen paper for edexcel, do you think that represents the paper wer going to get in any way and is it supposed to be easier or harder?
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    (Original post by TheProKi)
    I've just done C1 specimen paper for edexcel, do you think that represents the paper wer going to get in any way and is it supposed to be easier or harder?
    I don't know. Your paper could be anything, be ready for anything.
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    (Original post by Zacken)
    I don't know. Your paper could be anything, be ready for anything.
    Knowing edexcel they may even throw some c3 and c4 questions in there :P
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    (Original post by TheProKi)
    Knowing edexcel they may even throw some c3 and c4 questions in there :P
    They're not going to.
 
 
 
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