关于确界及确界原理的教学

ON THE TEACHING OF SUPREMUM AND INFIMUM

从给出确界的四个等价定义入手，通过例题分析，揭示了确界的内涵及应用确界原理的一般原则。

First,Giving four equivalent difinitions of supremum, then analyse examples, the writer bring to light the meaning of supremum and the general principle of applying supremum (infimum) principle.