1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

B Ellipse tangent line using projections

  1. Nov 19, 2017 #1
    Hi :)

    The question is in dutch so i'l translate it.

    on an ellipse E with vertex P and P' on the major axis and vertex Q and Q' on the minor axis. chose R(x1,y1), the projection of R on the major axis is R' and on the minor axis is R''. Define the perpendicular projection of the intrersection point of PR and P'R' on the major axis. And define the perpendicular projection of the intersection point of QR and Q'R'' on the minor axis. prove that the line drawn from these two projections is the tangent line of R.

    I Get stuck every time. Sorry if the awnser is obvious, i'm only 16. I attached a quick sketch i made and sorry if there are translation errors.


    kind regards Arthur

    this is the sketch
     
  2. jcsd
  3. Nov 19, 2017 #2

    andrewkirk

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Something must have got lost in translation. The line segment P'R' lies on the major axis and does not intersect the line segment PR. If we extend P'R' to intersect PR then it does so at P, which generates no new points.

    Similarly, Q'R'' lies on the minor axis and does not intersect QR'.

    I suggest posting a diagram.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Ellipse tangent line using projections
  1. Tangent line (Replies: 5)

  2. What is a tangent line (Replies: 0)

Loading...