Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

Parabola ; part 3 ques?

Q3.Two perpendicular chords are drawn from the origin 'O' to the parabola y = x^2 , which meet the parabola at P and Q .Rectangle POQR is completed . Find the locus of vertex of R.

2 Answers

Relevance
  • 1 decade ago
    Favorite Answer

    Abhinav i m doing the problem for y^2=4ax. We can get the answer to ur problem by making appropriate replacements at the end

    let t1 and t2 be the parameters of P and Q respectively. Then as OP and OQ are perpendicular, we get the relation t1t2=-4. Now let the coordinates of point R be (x,y)

    Now use the property of rectangle the diagonals bisect each other, so we get two relations

    at1^2+at2^2=x

    and 2at1+2at2=y

    now get the values of the redundant of these three equations is the req sol.

    Use the identity (t1+t2)^2=t1^2+t2^2+2t1t2

    At the last to get ur answer put a=1/4 and replace x by y and y by x

  • 5 years ago

    since y=x^2 so take paramateric as (x,x^2) at P and (x1,x1^2) at Q

    after that OP and OQ are perpendicular, so x*x1=-1 -------------------(1)

    then use the property of rectangle that the diagonals bisect each other

    so, x-1/x = h ---------(2)

    x^2+1/x^2 = K ----------------(3) where (h,k) is point at R

    square the equation (2) both side and replace it with equation (3)

    you get the answer h^2=k-2

Still have questions? Get your answers by asking now.