Results 1 to 4 of 4

Math Help - Bijection, Surjection, Injection or increasing function?

  1. #1
    Member
    Joined
    Oct 2008
    Posts
    93

    Bijection, Surjection, Injection or increasing function?

    Let f : R to R be a function.
    The statement (for all y in R)(there exists x in R) such that (f(x) = y) means that f is . . .

    increasing function, It might be the others but im not sure like a bijection can also be an increasing fucntion im just not sure how to distinguish what this is
    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
    Quote Originally Posted by treetheta View Post
    Let f : R to R be a function.
    The statement (for all y in R)(there exists x in R) such that (f(x) = y) means that f is . . .

    increasing function, It might be the others but im not sure like a bijection can also be an increasing fucntion im just not sure how to distinguish what this is
    It is not increasing. I'll give you a hint if w is the word you wish to find and \ell is the first letter of a word then i<\ell(w)

    Spoiler:
    If this is true then f(\mathbb{R})=\mathbb{R}
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Oct 2008
    Posts
    93
    Quote Originally Posted by Drexel28 View Post
    It is not increasing. I'll give you a hint if w is the word you wish to find and \ell is the first letter of a word then i<\ell(w)

    Spoiler:
    If this is true then f(\mathbb{R})=\mathbb{R}

    wait what's i, wait i think i get it it has to be a surjection then right!!! =D
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor Drexel28's Avatar
    Joined
    Nov 2009
    From
    Berkeley, California
    Posts
    4,563
    Thanks
    21
    Quote Originally Posted by treetheta View Post
    wait what's i, wait i think i get it it has to be a surjection then right!!! =D
    Correct!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Injection/Surjection
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: April 17th 2010, 10:13 PM
  2. Injection and Surjection
    Posted in the Advanced Algebra Forum
    Replies: 15
    Last Post: January 7th 2010, 06:44 AM
  3. injection, surjection and bijection questions
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: November 7th 2009, 10:23 AM
  4. injection/surjection/bijection questions
    Posted in the Discrete Math Forum
    Replies: 6
    Last Post: October 17th 2009, 12:09 PM
  5. injection & surjection proofs
    Posted in the Discrete Math Forum
    Replies: 2
    Last Post: April 15th 2009, 05:01 AM

Search Tags


/mathhelpforum @mathhelpforum