Real analysis
Lesson 1 of 10
Introduction
The epsilon–delta definition of a limit
Objective. State and use the formal definition of a limit.
- 1. Learn
- 2. Worked example
- 3. Practice
- 4. Feedback
- 5. Continue
Learn: the key idea
lim f(x) = L means: for every ε > 0 there is a δ > 0 such that 0 < |x − a| < δ implies |f(x) − L| < ε.
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