Results 1 to 4 of 4

Math Help - polynomial

  1. #1
    Newbie
    Joined
    Sep 2007
    Posts
    14

    Post polynomial

    help with another one please, Express as a polynomial.
    (x+a){x^2-ax/x}, my answer is x^2-2ax+a^2, but not sure if it could be x^2-2ax-a^2, thanks for checking.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,846
    Thanks
    320
    Awards
    1
    Quote Originally Posted by wayne View Post
    help with another one please, Express as a polynomial.
    (x+a){x^2-ax/x}, my answer is x^2-2ax+a^2, but not sure if it could be x^2-2ax-a^2, thanks for checking.
    If you've been doing factoring you should know how to multiply these out. (I mean, without relying on FOIL, but it depends on how you're being taught.)

    (x + a) \left ( \frac{x^2 - ax}{x} \right )

    = \frac{(x + a)(x^2 - ax)}{x}

    = \frac{x(x^2 - ax) + a(x^2 - ax)}{x}

    = \frac{(x^3 - ax^2) + (ax^2 - a^2x)}{x}

    = \frac{x^3 - a^2x}{x}

    = \frac{x(x^2 - a^2)}{x}

    = x^2 - a^2

    -Dan

    Edit: Or I suppose you could've simply done
    \frac{x^2 - ax}{x} = x - a
    immediately and multiplied out from there.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2007
    Posts
    14

    Smile I should have,

    so I should have x^2-a^2, thanks for looking this over.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,846
    Thanks
    320
    Awards
    1
    Quote Originally Posted by wayne View Post
    so I should have x^2-a^2, thanks for looking this over.
    No prob!

    -Dan
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: October 23rd 2011, 06:36 AM
  2. Replies: 1
    Last Post: February 24th 2011, 06:46 PM
  3. Replies: 1
    Last Post: December 15th 2009, 07:26 AM
  4. [SOLVED] dividing polynomial by a polynomial
    Posted in the Algebra Forum
    Replies: 1
    Last Post: February 3rd 2008, 02:00 PM
  5. dividing a polynomial by a polynomial
    Posted in the Algebra Forum
    Replies: 1
    Last Post: August 2nd 2005, 12:26 AM

Search Tags


/mathhelpforum @mathhelpforum