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Homework Help: My first question here help please

  1. Mar 11, 2010 #1
    Hello all

    Thses are my questions:


    1. Prove that if A(x) is a one to one odd function, then A^(-1) (x) is also odd function.





    2. If D(x) and R(x) are one to one functions, then
    (DoR)^(-1) (x)=(R^(-1) o D^(-1) )(x)


    I hope that someone will help me ^^
     
  2. jcsd
  3. Mar 11, 2010 #2

    Mark44

    Staff: Mentor

    You have to make an effort at proving these before anyone can give you any help.
     
  4. Mar 12, 2010 #3
    Actually, in general I want to know how to prove any question?
     
    Last edited: Mar 12, 2010
  5. Mar 12, 2010 #4
    How to prove any question? You have asked very difficult question. I think the best way is to experience it by looking at examples and solving problems, at least trying to solve.
    Some commonly used way to prove are

    (i)Solve L.H.S and the R.H.S, if both give same result then it is proved
    (ii) Solve either of L.H.S or R.H.S to prove other side.

    (iii) Prove it by making some contradiction
     
  6. Mar 12, 2010 #5
    How to prove any question? You have asked very difficult question. I think the best way is to experience it by looking at examples and solving problems, at least trying to solve.
    Some commonly used way to prove are

    (i)Solve L.H.S and the R.H.S, if both give same result then it is proved
    (ii) Solve either of L.H.S or R.H.S to prove other side.

    (iii) Prove it by making some contradiction
     
  7. Mar 13, 2010 #6
    Start by defining the terms used, writing them as equations if possible.

    What does it mean to say "A(x) is one to one"?
    What does it mean to say "A(x) is an odd function"?
    What is the definition of A^(-1) (x)?
     
  8. Mar 14, 2010 #7
    Thank you all
    Your advices were very helpful ^^
     
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