1. Not finding help here? Sign up for a free 30min 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!

Multivariable calculus question

  1. Oct 20, 2007 #1
    1. The problem statement, all variables and given/known data

    Sketch the following curves on separate number planes.

    y= 2x^2

    x^2 + 2y^2= 4

    2. Relevant equations



    3. The attempt at a solution

    For the first one, would the intersection of the curve with the y axis be at y=2 ( I have attached a diagram of my solution). The minimum point would be at (0,2)???

    For the second one, what do we do with the 2 which is the coefficient of y^2. Would the 4 be the radius of the circle.

    Thanks in advance.
     

    Attached Files:

  2. jcsd
  3. Oct 20, 2007 #2
    In the first one. If the curve was intersecting the y-axis, then x = 0 at the point of intersection, and so y = 0 aswell, so it intersects are (0,0). Also, the minimum point of the function is at (0,0).

    For the second one, are you sure that the equation you have describes a circle? I would call it an ellipse myself.
     
  4. Oct 20, 2007 #3
    oh alrite, but then what happens with the 2 in x^2 for the first equation. Yea, the second one is an ellipse so would 4 be the radius?? Cheers
     
  5. Oct 20, 2007 #4
    [tex] y = 2x^2 [/tex]
    if x = 0; [tex] y = 2*(0^2) = 0 [/tex]

    As for the ellipse. have you tried working out the values for x and y when the other one is set to 0? That will tell u where it crosses each axis.

    edit: This might help - http://en.wikipedia.org/wiki/Ellipse
     
    Last edited: Oct 20, 2007
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Multivariable calculus question
Loading...