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!

Finding the equation of a surface?

  1. Sep 15, 2012 #1
    1. The problem statement, all variables and given/known data

    2 Questions.

    1)Find an equation for the surface consisting of all points P for which the distance from P to the x-axis is 5 times the distance from P to the yz-plane.

    2)Find an equation for the surface consisting of all points that are equidistant from the point (−3, 0, 0) and the plane x = 3.

    2. Relevant equations



    3. The attempt at a solution

    1)The only thing I can think of is an ellipsoid with an equation similar to 5x^2+y^2+z^2=1

    Is that correct? Or am I totally off?

    2) I feel a parabolic cylinder would work here (opening facing toward point) but not sure how to find the equation.
     
  2. jcsd
  3. Sep 15, 2012 #2

    LCKurtz

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    In both cases take a variable point ##(x,y,z)##, calculate the various distances, and use the given relations. You will undoubtedly have to square things to simplify the equations.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook