Paper 1, Section II, G

Analysis II
Part IB, 2017

What does it mean to say that a real-valued function on a metric space is uniformly continuous? Show that a continuous function on a closed interval in R\mathbb{R} is uniformly continuous.

What does it mean to say that a real-valued function on a metric space is Lipschitz? Show that if a function is Lipschitz then it is uniformly continuous.

Which of the following statements concerning continuous functions f:RRf: \mathbb{R} \rightarrow \mathbb{R} are true and which are false? Justify your answers.

(i) If ff is bounded then ff is uniformly continuous.

(ii) If ff is differentiable and ff^{\prime} is bounded, then ff is uniformly continuous.

(iii) There exists a sequence of uniformly continuous functions converging pointwise to ff.