Results 1 to 4 of 4

Math Help - [SOLVED] Write parametric and symmetric equations for the z-axis.

  1. #1
    Newbie
    Joined
    Mar 2009
    Posts
    10

    [SOLVED] Write parametric and symmetric equations for the z-axis.

    This question just seems somewhat unclear.

    Asking for symmetric and parametric equations for the z axis means to have x and y equaling zero?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,547
    Thanks
    539
    Hello, TJ2988!

    Write the symmetric and parametric equations for the z axis.
    You are expected to know this. . .


    A line through P(x_1,y_1,z_1) with direction vector \vec v \:=\:\langle a,b,c\rangle has:

    . . Symmetric equation: . \frac{x-x_1}{a} \:=\:\frac{y-y_1}{b} \:=\:\frac{z-z_1}{c}

    . . Parametric equations: . \begin{Bmatrix}x &=& x_1+at \\ y &=& y_1 + bt \\ z &=& z_1 + ct\end{Bmatrix}



    We have: . P(0,0,0) and \vec v \:=\:\langle0,0,1\rangle

    . . Go for it!

    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Mar 2009
    Posts
    10
    Okay, so then the equations would be as follows:

    Symmetric:
    (x-0)/0 = (y-0)/0 = (z-0)/1

    Parametric:
    x=0
    y=0
    z=t

    Although the symmetric equations of x & y are 0 which is not allowed. So how would do you change it so they are not?
    Multiply all by zero to give x=y=0?

    Thank you very much for your help!
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor

    Joined
    Apr 2005
    Posts
    14,974
    Thanks
    1121
    Quote Originally Posted by TJ2988 View Post
    Okay, so then the equations would be as follows:

    Symmetric:
    (x-0)/0 = (y-0)/0 = (z-0)/1

    parametric:
    x=0
    y=0
    z=t

    Although the symmetric equations of x & y are 0 which is not allowed. So how would do you change it so they are not?
    Multiply all by zero to give x=y=0?
    Yes, that is exactly right.

    Thank you very much for your help!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Parametric and symmetric equations
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: February 26th 2011, 05:56 AM
  2. How do I do parametric and symmetric equations
    Posted in the Calculus Forum
    Replies: 3
    Last Post: April 21st 2010, 06:36 AM
  3. Symmetric to which axis?
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: August 14th 2008, 06:18 PM
  4. Replies: 2
    Last Post: June 8th 2008, 06:22 AM
  5. Parametric/Symmetric equations
    Posted in the Calculus Forum
    Replies: 1
    Last Post: April 17th 2008, 12:43 AM

Search Tags


/mathhelpforum @mathhelpforum