Antwort
1. $f(c)$ is defined; 2. $\lim_{x \to c} f(x)$ exists; 3. $\lim_{x \to c} f(x) = f(c)$.
Erklärung
Both one-sided limits $\lim_{x \to c^-} f(x)$ and $\lim_{x \to c^+} f(x)$ must exist and equal each other as well as $f(c)$.
Start / Bibliothek / CSAT (Suneung) essentials: original practice / Synthetische Lernkarte
What is the condition for a function $f(x)$ to be continuous at $x = c$?
Lernkarte aus dem Deck CSAT (Suneung) essentials: original practice.