Results 1 to 2 of 2

Math Help - Combining two equations by addition or multiplication?

  1. #1
    Newbie
    Joined
    Apr 2010
    Posts
    1

    Combining two equations by addition or multiplication?

    Hello all,

    I have a seemingly simple question concerning the combination of two quadratic equations:

    z(x) = x^2 + 2*x - 1

    z(y) = 2*y^2 + 3*y + 1

    What is the significance of combining these two equations by multiplying them together versus simply adding them together? I know if I take the product of the two equations, I will end up with a 2D surface described by equation z(x,y). But what is the difference between that and the equation obtained by adding them together, z(x,y)?

    Any insight on this will be much appreciated.

    Regards,
    smpaladin
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Aug 2007
    From
    USA
    Posts
    3,110
    Thanks
    2
    Your question is one of degree only.
    • Add quadratic to quadratic to get some other quadratic surface.
    • Multiply quadratic by quadratic to get a quartic surface of some sort.
    The actual meaning of the act would depend on your application.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: June 21st 2011, 06:41 AM
  2. Addition and Multiplication law of probablility
    Posted in the Statistics Forum
    Replies: 1
    Last Post: February 1st 2010, 03:34 PM
  3. lim sup and addition, multiplication
    Posted in the Calculus Forum
    Replies: 0
    Last Post: February 3rd 2009, 04:05 PM
  4. Addition and multiplication with Sets
    Posted in the Discrete Math Forum
    Replies: 2
    Last Post: December 10th 2007, 04:26 PM
  5. Equations - both addition and multiplication
    Posted in the Algebra Forum
    Replies: 4
    Last Post: February 26th 2006, 08:38 PM

Search Tags


/mathhelpforum @mathhelpforum