Results 1 to 4 of 4

Math Help - Parabola!!

  1. #1
    Newbie
    Joined
    Dec 2008
    Posts
    4

    Parabola!!

    Hey anyone got any ideas on how to solve this??
    Right I have done the first part: Is it possible for the tangents to a parabola at two distinct zeroes (x intercepts) to meet at right angles?
    But need help on:
    Is it possible to find such a parabola for which the x and y intercepts and the point of intersection of the two tangents lie on the integer lattice? What can you say about cubics?

    Thanks!! xx
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Aug 2008
    From
    Paris, France
    Posts
    1,174
    Quote Originally Posted by jessismith View Post
    Hey anyone got any ideas on how to solve this??
    Right I have done the first part: Is it possible for the tangents to a parabola at two distinct zeroes (x intercepts) to meet at right angles?
    But need help on:
    Is it possible to find such a parabola for which the x and y intercepts and the point of intersection of the two tangents lie on the integer lattice? What can you say about cubics?

    Thanks!! xx
    Do you have a classmate named Sonia? Because she asked the same questions in a previous thread (in the third post), and some answers were given, but only on the part you did...
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Dec 2008
    Posts
    4
    Yep I did search which gave me the answer to the first part (like stated in question) but the other questions were not answered. :-)
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,710
    Thanks
    630
    Hello, jessismith

    Is it possible for the tangents to a parabola at two distinct zeroes
    to meet at right angles?

    Is it possible to find such a parabola for which the x and y intercepts
    and the point of intersection of the two tangents lie on the integer lattice?

    What can you say about cubics?
    Here's a bit of parabolic trivia . . .

    The endpoints of a focal chord (a chord through the focus) have tangents
    . . which are perpendicular and intersect on the directrix.


    So if we place the focus at the origin . . .
    Code:
                  |
           *      |      *
                  |
            * A   |F  B *
          ---o----+----o-----
              \*  |  */
               \  *  /
                \ | /
                 \|/
          - - - - o - - - - -
                  |C

    Then the intercepts at A and B have tangents so that AC \perp BC.

    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Parabola
    Posted in the Geometry Forum
    Replies: 2
    Last Post: May 9th 2010, 12:20 AM
  2. parabola
    Posted in the Geometry Forum
    Replies: 1
    Last Post: January 19th 2010, 12:10 AM
  3. Parabola help please
    Posted in the Pre-Calculus Forum
    Replies: 4
    Last Post: January 16th 2010, 06:41 AM
  4. Parabola
    Posted in the Algebra Forum
    Replies: 1
    Last Post: November 25th 2008, 08:07 AM
  5. parabola
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: February 25th 2008, 01:52 PM

Search Tags


/mathhelpforum @mathhelpforum