18.04 Topic 3: Line Integrals and Cauchy's Theorem (MIT OCW lecture notes)
by Jeremy Orloff · MIT OpenCourseWare
Eleven-page lecture notes from MIT's undergraduate complex variables course. They define complex line integrals, cover path independence and antiderivatives, prove Cauchy's theorem using Green's theorem, and work through examples of closed contours that do or do not enclose singularities.
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