Stage 19 · Sets & Intervals — the Language of Functions
19.5.3 Half-Open and Infinite Intervals
19.5 Intervals and Neighborhoods: Sets on the Number Line
Point 3 of 5
19.5.3 Half-Open and Infinite Intervals
Core ideaInclude one end but not the other with (1,5]; for an end you can never reach, use +∞ or −∞.
Module goal. Carry the language of sets onto the number line, using intervals and neighborhoods to capture continuous ranges of numbers neatly — a direct route to the domain of a function