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Unit 2 · 8.2 · Functions & continuity

Limits & continuity

f is continuous at x0 if f(xk)→f(x0) for EVERY sequence xk→x0. Two paths with different limits prove discontinuity; a bound |f|≤g→0 proves continuity.

Unit 2 · 8.2
Formulas at a glance · Functions & continuity

Functions, graphs & level sets

Nc={(x1,x2)∈ℝ2:f(x1,x2)=c}

Limits & continuity

limk→∞f(xk)=f(limk→∞xk)=f(x0)