Stage 36 · Limits, Derivatives & Their Applications

36.1.1 From "Necessary and Sufficient" to "Infinitely Close"

36.1 The Art of Approaching: The Idea of a Limit

Point 1 of 5

36.1.1 From "Necessary and Sufficient" to "Infinitely Close"

Core idea

Last stage you judged whether things were close enough; now let that closeness keep going forever, and that's the arrow in x→a.

Module goal. Build the gut feeling of "getting infinitely close," turning the vague "closer and closer" into a precise, workable language of limits that sets the stage for rates of change.
eastmath.com · 36.1 The Art of Approaching: The Idea of a Limit · 36.1.1 From "Necessary and Sufficient" to "Infinitely Close"