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Analysis math help!

  • #1
1. Let E be a nonempty subset of R (real numbers)

Prove that infE <= supE

2. Prove that if a > 0 then there exists n element N (natural) such that 1/n < a < n

3. A subset E of te real numbers R is an inductive set if

i) 1 element E
ii) If x element E then x + 1 element E

A real number is called a natural number if it belongs to every inductive set. The set of natural numbers is denoted by N. Recall that the priciple of mathematical inductions says that if M is any subset of N that is an inductive set then M = N. Show that N = E, where E = {1,2,3,4...}

Any help would be greatly appreciated ! :)

Answers and Replies

  • #2
Please show us your attempt at a solution.
  • #3
i can not some up with anything i am not sure where to start for any of them
  • #4
Do you know the definitions of inf A and sup A ?

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