Editing Constructive analysis (section)

====Bounds and suprema====
Given such a model then enables the definition of more set theoretic notions. For any subset of reals, one may speak of an [[Upper and lower bounds|upper bound]] <math>b</math>, negatively characterized using <math>x\le b</math>. One may speak of least upper bounds with respect to "<math>\le</math>". A [[supremum]] is an upper bound given through a sequence of reals, positively characterized using "<math><</math>". If a subset with an upper bound is well-behaved with respect to "<math><</math>" (discussed below), it has a supremum.