Suppose $x$ is a non-negative real number such that for all $epsilon >0$ we have $x < epsilon$. Then...











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Is the following statement true?




Suppose $x$ is a nonnegative real number such that for all $epsilon >0$ we have $x < epsilon$. Then $x=0$.




Intuitively speaking yes since $0$ is an infimum of the set ${epsilon space|epsilon >0}$. I was trying to come up with an axiomatic reason for this but all I could find was algebraic properties of $0$ on $mathbb{R}$ which didn't seem too relevant. But can this result be derived from the order axioms of $mathbb{R}$ if true?










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    up vote
    1
    down vote

    favorite












    Is the following statement true?




    Suppose $x$ is a nonnegative real number such that for all $epsilon >0$ we have $x < epsilon$. Then $x=0$.




    Intuitively speaking yes since $0$ is an infimum of the set ${epsilon space|epsilon >0}$. I was trying to come up with an axiomatic reason for this but all I could find was algebraic properties of $0$ on $mathbb{R}$ which didn't seem too relevant. But can this result be derived from the order axioms of $mathbb{R}$ if true?










    share|cite|improve this question


























      up vote
      1
      down vote

      favorite









      up vote
      1
      down vote

      favorite











      Is the following statement true?




      Suppose $x$ is a nonnegative real number such that for all $epsilon >0$ we have $x < epsilon$. Then $x=0$.




      Intuitively speaking yes since $0$ is an infimum of the set ${epsilon space|epsilon >0}$. I was trying to come up with an axiomatic reason for this but all I could find was algebraic properties of $0$ on $mathbb{R}$ which didn't seem too relevant. But can this result be derived from the order axioms of $mathbb{R}$ if true?










      share|cite|improve this question















      Is the following statement true?




      Suppose $x$ is a nonnegative real number such that for all $epsilon >0$ we have $x < epsilon$. Then $x=0$.




      Intuitively speaking yes since $0$ is an infimum of the set ${epsilon space|epsilon >0}$. I was trying to come up with an axiomatic reason for this but all I could find was algebraic properties of $0$ on $mathbb{R}$ which didn't seem too relevant. But can this result be derived from the order axioms of $mathbb{R}$ if true?







      real-numbers ordered-fields






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      edited Nov 14 at 21:55









      José Carlos Santos

      140k19111204




      140k19111204










      asked Nov 14 at 21:46









      Sei Sakata

      567




      567






















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          If $x>0$, take $varepsilon=x$. Then $x<varepsilon=x$, which is impossible.






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            If $x>0$, take $varepsilon=x$. Then $x<varepsilon=x$, which is impossible.






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              up vote
              2
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              If $x>0$, take $varepsilon=x$. Then $x<varepsilon=x$, which is impossible.






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                up vote
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                If $x>0$, take $varepsilon=x$. Then $x<varepsilon=x$, which is impossible.






                share|cite|improve this answer












                If $x>0$, take $varepsilon=x$. Then $x<varepsilon=x$, which is impossible.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Nov 14 at 21:48









                José Carlos Santos

                140k19111204




                140k19111204






























                     

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