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Question about a logic notation

  1. Aug 27, 2011 #1
    (x∈R → f(x)>0) → f is asmani.

    What does it mean:

    1. If there exists some x in R such that f(x)>0, then f is asmani.

    2. If for all x in R we have f(x)>0, then f is asmani.

    3. It's ambiguous or meaningless.

    4. ...?

    Thanks in advance.
     
    Last edited: Aug 27, 2011
  2. jcsd
  3. Aug 27, 2011 #2

    tiny-tim

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    2. If for all x in R we have f(x)>0, then f is asmani. :smile:
     
  4. Aug 27, 2011 #3

    HallsofIvy

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    And now I am going to spend all day wondering what "asmani" means!
     
  5. Aug 27, 2011 #4
    Thanks. Is that a common formulation?
    asmani means skiey (or of sky) in Persian, although I didn't mean that!
     
    Last edited: Aug 27, 2011
  6. Aug 27, 2011 #5
    I think it means always positive. Frankly, I have never seen that word.
     
  7. Aug 28, 2011 #6

    tiny-tim

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    not sure i understand you :confused:

    that is the only interpretation of your original formula :smile:
    haha! :biggrin:

    as a matter of interest, does "armani" mean anything in Persian?
     
  8. Aug 28, 2011 #7
    I mean the original formula. Is that a common formulation in order to say "If for all x in R we have f(x)>0, then f is asmani"?
    Yes, it means "ideal". :smile:
     
  9. Aug 28, 2011 #8

    tiny-tim

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    yes, that is a standard form of definition

    eg: "if, for all non-zero vectors x, xTAx > 0, then A is positive definite" :wink:
     
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