C4 parametric equation

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  1. alexlct054's Avatar
    • Junior Member
    • Posts: 29
    C4 parametric equation
    I manage to do the part(i)-part(iii) but I reli dun know how to do the question(iv).

    part(iv) The point Q is the intersection of the line x=1/2 and the straight line joining the origin to the point T. Point R has co-ordinates(1/2,0).
    Show that RQ=QP.

    as I couldn't find the point T, so I couldn't find the y co-ordinates of Q. Can anyone help me pls? Thanks a lot!!
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  2. Aurum's Avatar
    • Full Member
    • Posts: 127
    Re: C4 parametric equation
    T is not a fixed point, it is a general point on the curve with co-ordinates, (1/1+t),(1/(1+t)(1-t)). t can take any value, the final result RQ=QP holds for any value of t except -1.1, like t=-3,-2,0,2,3 etc.

    Now you know what T is and since you've done part (iii), I trust you can now find the y-coordinate of Q. Then you can prove RQ=QP.
    Last edited by Aurum; 24-03-2012 at 18:09.
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