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C2 and Implicit Differnatiation, yes or no? watch

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    I'm currently studying for my A2's but I'm retaking C2, and I was doing some past papers and got a question to find the equation of a tangent to a circle. I used implicit differentiation to achieve dy/dx and find the gradient and hence finding the equation of the tangent. The answer was correct, but, am I allowed to use implicit differentiation in C2 to find the eq. of the tangent? Will I lose marks?

    Thanks for the help
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    OP, any mathematically valid approach will be awarded marks as long as the correct answer(s) is/are obtained.

    The markers will have an extended MS with various possible methods.
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    If it asks you to do it a certain way then you have to do it that way. Otherwise just make sure you're clear about what you're doing and it's fine.
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    (Original post by Kvothe the arcane)
    I am confused, any mathematically valid approach will be awarded marks as long as the correct answer(s) is/are obtained. The markers will have an extended MS full of various possible methods.
    Sorry, I forgot to mention it but implicit differentiation is only part of the A2 course, which is why I am confused, I thought I couldn't just use this method, and I would have had to use the method they want, otherwise wouldn't I lose a method mark? Or is this method acceptable?

    Thanks for your reply
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    (Original post by IAmConfused1)
    Or is this method acceptable?
    It is acceptable.
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    (Original post by IAmConfused1)
    Sorry, I forgot to mention it but implicit differentiation is only part of the A2 course, which is why I am confused, I thought I couldn't just use this method, and I would have had to use the method they want, otherwise wouldn't I lose a method mark? Or is this method acceptable?
    Unless it asks you to do it via a certain method, then it's fine.
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    (Original post by Zacken)
    It is acceptable.
    (Original post by Kvothe the arcane)
    Unless it asks you to do it via a certain method, then it's fine.
    I'll carry on using my method then, thanks for your help.
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    (Original post by Zacken)
    It is acceptable.
    However if OP makes a mistake, it's not as easy to gain method marks right?
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    it will be condoned
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    (Original post by Student403)
    However if OP makes a mistake, it's not as easy to gain method marks right?
    :yes:
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    (Original post by IAmConfused1)
    I'm currently studying for my A2's but I'm retaking C2, and I was doing some past papers and got a question to find the equation of a tangent to a circle. I used implicit differentiation to achieve dy/dx and find the gradient and hence finding the equation of the tangent. The answer was correct, but, am I allowed to use implicit differentiation in C2 to find the eq. of the tangent? Will I lose marks?

    Thanks for the help
    You could make a theorem up in the exam and as long as you've given the correct answer you'll get your marks

    for edexcel
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    (Original post by Student403)
    However if OP makes a mistake, it's not as easy to gain method marks right?
    Still should be fine.

    Here's an example from a C2 Edexcel MS. The question was to find the equation of the tangent to a circle at a given point, where you're given the centre of the circle.

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    (Original post by LelouchViRuge)
    You could make a theorem up in the exam and as long as you've given the correct answer you'll get your marks

    for edexcel
    You'd have to prove the theorem.
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    (Original post by notnek)
    Still should be fine.

    Here's an example from a C2 Edexcel MS. The question was to find the equation of the tangent to a circle at a given point, where you're given the centre of the circle.

    Interesting to know - thank you!
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    (Original post by notnek)
    Still should be fine.

    Here's an example from a C2 Edexcel MS. The question was to find the equation of the tangent to a circle at a given point, where you're given the centre of the circle.
    Is that a public MS?
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    (Original post by Zacken)
    Is that a public MS?
    Yes. June 08.
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    (Original post by notnek)
    Yes.
    I see, the markschemes seem to vary in detail from module to module. :lol:
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    (Original post by Zacken)
    I see, the markschemes seem to vary in detail from module to module. :lol:
    For exams that have an actual meeting for markers, a lot will be said that may not be written in the mark scheme. For exams where the standardisation of markers is done entirely online (not an online meeting), much more needs to be written in the mark scheme.
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    (Original post by tiny hobbit)
    For exams that have an actual meeting for markers, a lot will be said that may not be written in the mark scheme. For exams where the standardisation of markers is done entirely online (not an online meeting), much more needs to be written in the mark scheme.
    Ah, okay. I see - so I'm guessing that the core papers have meetings and the mechanics one are done online?
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    Should be alright - I did implicit differentiation in my GCSEs so I found it helpful as well. It's probably best to say you're differentiating with respect to x so that you're making things clear for the marker. Besides, implicit differentiation is allowed in FP1 even though you learn it in a later module (that being C4).
 
 
 
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