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Imaginary Numbers Are Real [Part 1: Introduction]

A 6-minute video by Welch Labs about mathematical reasoning, on the Mathematics shelf. It came up in r/math, in a thread called “What are some of your favorite math explainer videos that aren’t from mathologer, numberphile, or 3b1b?”.

Welch Labs, Video, 6 min, 2015, on the Mathematics shelf