Results 1 to 2 of 2

Math Help - left inverse equivalent to inverse

  1. #1
    Member
    Joined
    Oct 2010
    Posts
    131

    left inverse equivalent to inverse

    Hello,

    in our lecture the professor said, if a nxn-Matrix M has a left inverse M'*M=I. Then M is invertible.
    How can i prove it? I think it is not so easy, since i couldn't solve the problem.

    Oh my god. Now i have solved the problem unexpectedly.
    Therefore you don't need to answer.

    Regards
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor Drexel28's Avatar
    Joined
    Nov 2009
    From
    Berkeley, California
    Posts
    4,563
    Thanks
    21

    Re: left inverse equivalent to inverse

    Quote Originally Posted by Sogan View Post
    Hello,

    in our lecture the professor said, if a nxn-Matrix M has a left inverse M'*M=I. Then M is invertible.
    How can i prove it? I think it is not so easy, since i couldn't solve the problem.

    Oh my god. Now i have solved the problem unexpectedly.
    Therefore you don't need to answer.

    Regards
    Just out of curiosity, which proof did you use? There are three I can think of.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Left Inverse
    Posted in the Discrete Math Forum
    Replies: 3
    Last Post: February 14th 2011, 02:24 PM
  2. Left inverse of matrix
    Posted in the Advanced Algebra Forum
    Replies: 3
    Last Post: October 10th 2010, 10:42 AM
  3. secant inverse in terms of cosine inverse?
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: August 30th 2010, 09:08 PM
  4. inverse trig values and finding inverse
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: April 6th 2009, 01:04 AM
  5. Semigroup with left id and inverse
    Posted in the Advanced Algebra Forum
    Replies: 1
    Last Post: August 26th 2008, 10:45 PM

Search Tags


/mathhelpforum @mathhelpforum