Results 1 to 4 of 4

Math Help - Matricies

  1. #1
    Junior Member
    Joined
    Feb 2009
    Posts
    39

    Matricies

    Show that if A and B are two n x n matricies with inverses A^{-1} and B^{-1}, then AB has an inverse and that (AB)^{-1} = B^{-1} A^{-1}
    Last edited by mr fantastic; August 19th 2009 at 04:50 AM. Reason: Fixed latex. Exponents require {} not ()
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by manalive04 View Post
    Show that if A and B are two n x n matricies with inverses A^{-1} and B^{-1}, then AB has an inverse and that (AB)^{-1} = B^{-1} A^{-1}
    Calculate (AB) (B^{-1} A^{-1}) and (B^{-1} A^{-1}) (AB). What do you find?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Feb 2009
    Posts
    39

    matricies

    Quote Originally Posted by mr fantastic View Post
    Calculate (AB) (B^{-1} A^{-1}) and (B^{-1} A^{-1}) (AB). What do you find?

    please explain this further i dont understand - sorry
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by manalive04 View Post
    please explain this further i dont understand - sorry
    There's nothing further to explain .... Do the matrix multiplications!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Matricies, need help...
    Posted in the Advanced Algebra Forum
    Replies: 5
    Last Post: November 26th 2010, 01:38 PM
  2. matricies
    Posted in the Algebra Forum
    Replies: 0
    Last Post: May 27th 2010, 06:57 PM
  3. Matricies
    Posted in the Algebra Forum
    Replies: 1
    Last Post: December 18th 2008, 09:46 AM
  4. Help with Matricies
    Posted in the Advanced Algebra Forum
    Replies: 3
    Last Post: October 26th 2008, 01:57 PM
  5. Another set of matricies, but a different way of doing it.
    Posted in the Advanced Algebra Forum
    Replies: 1
    Last Post: January 31st 2008, 08:25 PM

Search Tags


/mathhelpforum @mathhelpforum