6 Real line [09X]

We will indicate in the following with \(ℝ\) the real line, and with \(\overline{ℝ}=ℝ∪\{ +∞,-∞\} \) its extension. ¹

We will use intervals (see definition in [07C]↺↻).

E24

[09Y]↺↻

E24

[20V]↺↻

E24

[20W]↺↻

E24

[20X]↺↻

E24

[0B0]↺↻

6.1 Neighbourhoods

[29H]↺↻

6.2 Frequently, eventually

[29K]↺↻

6.3 Supremum and infimum

[29M]↺↻

6.4 Limits

[29N]↺↻

6.5 Upper and lower limits

[29P]↺↻

6.6 Approximation of irrational numbers

[29Q]↺↻