Visual Complex Analysis: 25th Anniversary Edition
by Tristan Needham · Oxford University Press
Needham replaces opaque computation with geometric argument across 501 diagrams, treating power series, the disc of convergence, and analytic continuation visually. Answers the 'why' that computational treatments skip — why a power series has a disc rather than an interval of convergence, and why the nearest singularity sets the radius. Paperback edition adds captions explaining each figure plus a Penrose foreword.
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