4:26 PM
My best guess is the the new tag was created by mistake and the intention was to use - I'll edit the post.
1

We know that : Let $\mathbb{R}$ denote the set of all real numbers. Then: 1-) The set $\mathbb{R}$ is a field, meaning that addition and multiplication are defined and have the usual properties. 2-)The field $\mathbb{R}$ is ordered, meaning that there is a total order ≥ such that, ...