Lemma 42 1101If an is a rational Cauchy sequence which does

Lemma 4.2. 1101/If an is a rational Cauchy sequence which does not tend to 0, then there enst a positive EQ and no EN such that either

Solution

proof is simply by the definition of cauchy sequence . if the sequence does converge to zero then there exist such delta such that an is < delta for every n >= N. The statment is just the contraposition of the statemen