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Graph a 2-sphere on graphcalc

  1. Jul 18, 2005 #1
    i attempted to graph a 2-sphere on graphcalc and it wouldn't work. the equations had to be in terms of z, so i had to use: [tex]z=\sqrt{-x^2-y^2+9}[/tex] and [tex]z=-\sqrt{-x^2-y^2+9}[/tex]. i thought that would give me a 2-sphere at the origin with a radius of 3, but it didn't. i got:[PLAIN]http://photobucket.com/albums/a192/YoDizzle/th_almostsphere.bmp.[/URL] [Broken] what did i do wrong?

    the split is along the x y plane. if it matters, this is my first try at using graphcalc.
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Jul 18, 2005 #2
    You got a sphere. It just breaks down near the xy-plane, because the approximations get fuzzy as the slope becomes very large. Your program only evaluates the function value on a small grid of points.
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