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    Imaginary Numbers Are Real [Part 1: Introduction]

    Welch Labs

    7 HN recommenders · recommended in 9 months, 2017–2025

    YouTube

    5:47 · 8.6M views · Aug 28, 2015

    The first part of Welch Labs' series on imaginary numbers, presenting them as the natural extension of the number line into two dimensions. It covers the history and the math with strong visuals.

    HN commenters rate the series as some of the best visual teaching on complex numbers and recommend it for building intuition.

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    9 comments from Hacker News

    1. @tails4eOct 2022· in “The paper that keeps showing up”

      Yes, the name imaginary does it no favours. I was confused for so long about i, as it was never explained on classes, and it wasn't until 3blue1brown and other math youtubers showed me the light. I really like this series on it by Welch Labs - loads of easily digestible videos, and a history lesson to boot: this video

      Strongly recommendsView on HN
    2. @pedrodelfinoAug 2017· in “Imaginary Numbers Are Real – YouTube Series”

      The greatest audiovisual content on the topic I have ever seen: Part 1 - this video Part 2 - [LINK] Part 3 - [LINK] Part 4 - [LINK] Part 5 - [LINK] Part 6 - [LINK] Part 7 - [LINK] Part 8 - [LINK] Part 9 - [LINK] Part 10 - [LINK] Part 11 - [LINK] Part 12 - [LINK] Part 13 - [LINK]

      Strongly recommendsView on HN
    3. @rrauenzaDec 2017· in “What are the complex numbers, really?”

      Welch Labs has a wonderful series on youtube on imaginary numbers, "Imaginary Numbers Are Real": this video I like to tell my kids that imaginary numbers aren't really imaginary .. that in many ways they're more real than the Reals.

      Strongly recommendsView on HN
    4. @wodenokotoSep 2021· in “A layman’s guide to recreational mathematics videos”

      Welch labs has an amazing series on complex numbers called “imaginary numbers are real”. Great explanations, engaging content and high production value. this video

      Strongly recommendsView on HN
    5. @wanderingmooseJan 2025· in “Quaternions and spherical trigonometry”

      I really like the welch labs series on imaginary numbers which covers the first part of what you talk about -- leveling up the notion of what a complex number is. Though his focus was more on solving simple equations with no real roots, but really detailing how/what is really going on. It is a great precursor to then thinking about quaternions this video

      RecommendsView on HN