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    Maths Questions- Parametrics

    Hi greenlemings, I confess to being a newby both to this forum and parametric equations, however my study to date leads me to offer the following solutions and also to refer you to this document which I have found invaluable in my learning...
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    Parabola - Parametric to Cartesian Conversion (2 more)

    I would really appreciate it if someone could review my answers for 1c) and 2c). I think i have taken the correct approaches but would like to be sure. 1 c) (i) Convert R(a(p+q),apq) to Cartesian where pq = -2 Sub for pq in y = apq => y = -2a (ii) Convert R(a(a+p),apq) to...
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    Parabola - Parametric to Cartesian Conversion (2 more)

    Thanks Integrand for the quick response. I thought that might be the case as in 1ci) and 1ciii) I could not get real values when solving for p & q simultaneously between (i) & (iii). But I thought I would seek expert opinion before continuing. I will now return to the problem and see how I go...
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    Parabola - Parametric to Cartesian Conversion (2 more)

    Hi, I had been progressing well with my understanding of parametrics until these two questions arose. The questions in full are: 1) Tangents to the parabola x^2 = 4ay at the points P(2ap,ap^2)and Q(2aq,aq^2) meet at R. a) Show that the equation of the tangent at P is y - px + ap^2 = 0...
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    Parabola - Parametric to Cartesian Conversion

    Ah, the wonders of the mighty computer over the visualisation of my mind. You are indeed correct and I have been chasing a phantom all this time. I had the correct answer all the time. Looks like my time would have been better spent learning to use GeoGebra. Many thanks for your graphical...
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    Parabola - Parametric to Cartesian Conversion

    My question arises from the following: The normal at any point P (2at,at^2) on the parabola x^2 = 4ay cuts the y -xis a Q and is projected to R so that PQ=QR A) Find the coordinates of R in terms of t. My answer at this point is R(-2at,at^2 + 4a) ) I arrived at that by identifying the...
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    Parabola - Parametric to Cartesian Conversion

    InteGrand, Therein lies the problem. The parabola thus defined is open at the top and I know the locus of the point is on an inverted parabola as I have physically drawn a sketch to confirm the locus. Graeme
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    Parabola - Parametric to Cartesian Conversion

    Hi, I am working on a problem where I know a point (-2at,at^2 +4a) lies on an inverted parabola about the y-axis. Normally I would transform x = -2at to t = -x/2a and then sub for t in y = at^2 + 4a to get to the Cartesian form. But this does not work in this instance. I think it has...
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