In this video I show how to calculate the eigenvalues and eigenvectors of a 2x2 matrix A, and show how to find a diagonal matrix D and an invertible matrix P such that A = PDP^-1

This delightful problem comes from a German math competition. What's the perimeter of the triangle CDE? You have 3 minutes to solve this problem. Watch the video for a solution, and to see the shape-shifting triangle hidden in this problem.

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Derivative of arctan(x-sqrt(x^2+1)) equals to the derivative of 1/2*arctan(x), but are the functions equation to each other?


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Programa de Aperfeiçoamento para Professores de Matemática do Ensino Médio - Julho / 2018 Perguntas e respostas Playlist dos videos: https://goo.gl/WeZZaM Pá...

How to graph a piecewise function? This question is an exercise from Stewart Calculus textbook. Sect2.5 #20. Please subscribe and share my videos to help my ...

In this video, I give a general (and non-technical) overview of the topics covered in an elementary complex analysis course, which includes complex numbers, complex functions, the Cauchy-Riemann equations, Cauchy’s integral formula, residues and poles, and…

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Limiting function of continuous…

In honor of approximate pi-day (22/7), in this video I show, without using a calculator (!), why pi must be less than 22/7. It all relies on calculating an i...

Investigate f(x)=x+abs(x), which is secretly a piecewise function, and its derivative. We will see that another continuous function does not have continuos derivative.

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Link to the tweet: https://twitter.com/blackpenredpen/status/1021116240130072577 ***you must retweet the tweet with your answers by July 25, 2018, 12:00pm PS...

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Thanks to Tyler Cenko, and Caio Cerqueira from Brazil, for suggesting this wonderful number puzzle! I had a lot of fun solving this. Can you make 6 from 3 copies of the same number, where the number ranges from 0 to 10? You can use common mathematical operations…

part1: derivative of sin(x) and cos(x), https://youtu.be/j1n6AMuMQso part2: derivative of tan(x) and cot(x), https://youtu.be/-9BVw_r6qmo part3: derivative o...

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This video recounts a lecture by Richard Feynman giving an elementary demonstration of why planets orbit in ellipses. See the excellent book by Judith and David Goodstein, "Feynman's…

Shapes have meaning. That may sound crazy, but hear me out. Let's explore how cinematographers and directors create shapes inside the frame to add visual storytelling to their films.

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TUG 2018 - Presentations covering the TeX world - Typesetting, fonts, publishing, … July 20-22, 2018 - The 39th Annual Meeting of the TeX Users Group Teacher...

TUG 2018 - Presentations covering the TeX world - Typesetting, fonts, publishing, …
July 20-22, 2018 - The 39th Annual Meeting of the TeX Users Group
Speaker: Eduardo Ochs - Dednat6: an extensible (semi-)preprocessor for LuaLaTeX that understands diagrams…

TUG 2018 - Presentations covering the TeX world - Typesetting, fonts, publishing, … July 20-22, 2018 - The 39th Annual Meeting of the TeX Users Group Teacher...

TUG 2018 - Presentations covering the TeX world - Typesetting, fonts, publishing, … July 20-22, 2018 - The 39th Annual Meeting of the TeX Users Group Teacher...

TUG 2018 - Presentations covering the TeX world - Typesetting, fonts, publishing, … July 20-22, 2018 - The 39th Annual Meeting of the TeX Users Group Teacher...