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    Usually in Maths exams, for AQA, i find when it asks me to Differentiate a function then find the stationary points, in the mark scheme Im only supposed to take the positive value, e.g. X^2 = 4 so X = 2 but shouldn't I take the negative as well?
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    Check the domain of the function.
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    (Original post by SunDun111)
    Usually in Maths exams, for AQA, i find when it asks me to Differentiate a function then find the stationary points, in the mark scheme Im only supposed to take the positive value, e.g. X^2 = 4 so X = 2 but shouldn't I take the negative as well?
    Post the question.
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    (Original post by SunDun111)
    Usually in Maths exams, for AQA, i find when it asks me to Differentiate a function then find the stationary points, in the mark scheme Im only supposed to take the positive value, e.g. X^2 = 4 so X = 2 but shouldn't I take the negative as well?
    Assuming ur talking bout shape questions, u have to take the positive value of x for obvious reasons

    otherwise like big E said above check da domain

    gl
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    (Original post by Zacken)
    Post the question.
    (Original post by Goatt)
    Assuming ur talking bout shape questions, u have to take the positive value of x for obvious reasons

    otherwise like big E said above check da domain

    gl
    dm read the question wrong thought it said x^2 = 4 it says x^1/2 = 4, but if your finding the equation of the normal at a stationary point, I think for the question X = 4 and Y = 8, wouldn't the equation by Y = 8, the mark scheme says X = 4
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    (Original post by SunDun111)
    dm read the question wrong thought it said x^2 = 4 it says x^1/2 = 4, but if your finding the equation of the normal at a stationary point, I think for the question X = 4 and Y = 8, wouldn't the equation by Y = 8, the mark scheme says X = 4
    ..
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    (Original post by SunDun111)
    dm read the question wrong thought it said x^2 = 4 it says x^1/2 = 4, but if your finding the equation of the normal at a stationary point, I think for the question X = 4 and Y = 8, wouldn't the equation by Y = 8, the mark scheme says X = 4
    blud we need infoooo like the function ur working with

    & this point u refer to
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    (Original post by SunDun111)
    dm read the question wrong thought it said x^2 = 4 it says x^1/2 = 4, but if your finding the equation of the normal at a stationary point, I think for the question X = 4 and Y = 8, wouldn't the equation by Y = 8, the mark scheme says X = 4
    What paper is it gg
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    (Original post by SunDun111)
    dm read the question wrong thought it said x^2 = 4 it says x^1/2 = 4, but if your finding the equation of the normal at a stationary point, I think for the question X = 4 and Y = 8, wouldn't the equation by Y = 8, the mark scheme says X = 4
    What does the normal look like at a stationary point? Does it look like a vertical line or a horizontal line? What does the tangent look like?
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    (Original post by Goatt)
    blud we need infoooo like the function ur working with

    & this point u refer to
    (Original post by Goatt)
    What paper is it gg
    June 2011 , C2 diff question, Q5.
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    (Original post by Zacken)
    What does the normal look like at a stationary point? Does it look like a vertical line or a horizontal line? What does the tangent look like?
    Verticle... Ohhhh ok so would it be X = 4 instead?
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    (Original post by SunDun111)
    Verticle... Ohhhh ok so would it be X = 4 instead?
    Yes.
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    (Original post by SunDun111)
    June 2011 , C2 diff question, Q5.
    [4,8] is the max that is right

    What you need to do now is find the slope of the tangent at the point M then use the normal is perpendicular rule
 
 
 
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