Examples on how to give a proof or a counterexample of a statement

Question

Examples; Prove or give a counterexample of the following statements,with quantifiers:

1) For each non-negative number s, there exists a non-negative number t such that s≥t

2) For each non-negative number t, there exists a non-negative number s such that s≥t

How could i proceed?

This holds if only if s<=t and t<=s! – Jianluca Apr 07 '15 at 17:53 — Jianluca, Apr 07 '15 at 17:53

score 1 · Accepted Answer · answered Apr 07 '15 at 17:50

1

$$ (\forall s\geq 0)(\exists t\geq 0)(s\geq t\land (\forall t\geq 0)(\exists s\geq 0)(s\geq t))\to (s=t) $$

answered Apr 07 '15 at 17:50

Daniel W. Farlow

@Jyanluka You should ask that as a separate question. :) – Daniel W. Farlow Apr 07 '15 at 18:20
Oops sorry for the mistake! – Jianluca Apr 07 '15 at 19:26

1 Answers1