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Homework Help: Describe geometrically the level surfaces of the functions

  1. Apr 29, 2010 #1
    So the question is as titled

    i) f=(x^2 +y^2 +z^2) ^1/2

    if I can figure out the method I can solve the other equations but I'm not really sure where to start I know that a function f(x,y,z) of a level surface well be constant so do I just find del f ?
     
  2. jcsd
  3. Apr 29, 2010 #2

    HallsofIvy

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    No, this has nothing to do with the gradient. A "level surface" for any function f(x,y,z) is, as you say, the set of points (x, y, z) where f(x, y, z)= C, a constant.

    Here, that gives [itex](x^2+ y^2+ z^2)^{1/2}= C[/itex]. What do you get if you square both sides?
     
  4. Apr 29, 2010 #3
    so you just square both sides so id get

    x2+y2+z2= C2

    where C2 is just another constant

    is that right?
     
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