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    (Original post by Ripper Phoenix)
    okay and what if it said parallel to x axis?
    numerator zero.
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    Could someone please post the June 2015 C34 ial mark scheme please!
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    (Original post by Humbers)
    Ok so when the tangent is parallel to the Y- axis, it means the tangent is vertical and therefore has an 'infinite' gradient

    The expression for dy/dx is -(2x+4y)/(4x+2y) for dy/dx = infinity the denominator must be equal to zero as anything divided by zero is undefined/infinite

    so then you get 4x + 2y = 0 y = -2x substitute that into the original equation to solve and get the co-ordinates
    okay but what about the tangent parallel to the x axis? then?
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    (Original post by MasonPye)
    Could someone please post the June 2015 C34 ial mark scheme please!
    here are the solutions https://a48aca6bcd82b5ada594d7397b73...%20koli248.pdf
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    (Original post by TeeEm)
    numerator zero.
    aha okay...

    you're a man of very few words

    but my teacher said we equate dy/dx to zero if it is parallel to x axis.. is this incorrect?
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    (Original post by marco cb)
    Yep, before I head to school, any last key points to remember in the exam, anyone?
    if in doubt, walk out


    jk you gotta pass, we all gotta pass!! good luck!!!!
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    (Original post by marco cb)
    Yep, before I head to school, any last key points to remember in the exam, anyone?
    iboprufen, imodium, glucose tablets, indigestion tablets, asthma pump (optional), water, tissues, toilet paper, disinfecting gel, ...
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    (Original post by Ripper Phoenix)
    okay but what about the tangent parallel to the x axis? then?

    Parallel to the x-axis means a horizontal line, so no gradient.

    therefore the numerator must be equal to zero
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    (Original post by TeeEm)
    look at related rates book Q30
    Do they have to ask for permission or something? or do they just swap values and rip the Q off you?
    Spoiler:
    Show
    got a related rates Q in particular that you would advise I do before todays exam? Found the one in question above fine - although i did not connect it in the long chain of 3 if that makes sense, I brought out the dv/da separately
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    (Original post by Ripper Phoenix)
    aha okay...

    you're a man of very few words

    but my teacher said we equate dy/dx to zero if it is parallel to x axis.. is this incorrect?
    when I was at school (Year 7) we used to chant ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
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    (Original post by Ripper Phoenix)
    aha okay...

    you're a man of very few words

    but my teacher said we equate dy/dx to zero if it is parallel to x axis.. is this incorrect?
    Yes dy/dx would equal zero

    in this case the only way dy/dx can = 0 is if the numerator is equal to zero as you can never divide something to get zero
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    (Original post by asjdj)
    When you realize you're on your period few hours before the exam.. nooooooooooooooooooooooooooooooo ooooooooooooo
    wtf?
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    Looks like I got 62/63 marks in C3, if Arsey's right and 64 marks is 90UMS there's still some hope for an A*, here's to hoping
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    (Original post by Ripper Phoenix)
    if in doubt, walk out


    jk you gotta pass, we all gotta pass!! good luck!!!!
    If I see a tricky ass question 1 that I can't answer, I will most likely have no option but to walk out. But ha thanks - Good luck to you too!
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    Can someone explain to me how to reflect a point in a line please?
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    (Original post by TeeEm)
    iboprufen, imodium, glucose tablets, indigestion tablets, asthma pump (optional), water, tissues, toilet paper, disinfecting gel, ...
    Check, check and check.. ran out of toilet paper though,
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    (Original post by Gilo98)
    Do they have to ask for permission or something? or do they just swap values and rip the Q off you?
    Spoiler:
    Show
    got a related rates Q in particular that you would advise I do before todays exam? Found the one in question above fine - although i did not connect it in the long chain of 3 if that makes sense, I brought out the dv/da separately
    triple rate is the sensible way, although it can be done as a double
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    Does anyone have any tips for sketching vector diagrams to make them easier to understand? Vectors are the one area I just can't seem to get my head round...
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    (Original post by TeeEm)
    when I was at school (Year 7) we used to chant ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
    if a fraction equal zero the only thing that can make it zero is its numerator ...
    i really need to meet you in real life :rofl3::rofl3::rofl::rofl::rofl::rofl:

    thanks tho
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    (Original post by marco cb)
    Check, check and check.. ran out of toilet paper though,
    what if you get the sh..., you run to the toilet and there is none?
 
 
 
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