/sci/ - Science & Math

>>8786751
>tfw you don't need drugs because you are already high on mathematics

We are one level above you, brainlet.

I was watching today's Wildberger video and at some point he decided to play the game of the reals. He decided to solve a problem in complex numbers using the usual methods taught at universities instead of his patented method.

This involved calculating an angle and for that he needed to compute the arctan function of [math] \frac{12}{5} [/math] and he used used the series
[math] \arctan(x)=x-\frac{x^3}{3}+\frac{x^5}{5}-\frac{x^7}{7}+\dots [/math]

But then he said that actually this series diverged for the number [math] \frac{12}{5} [/math]. But that makes no sense. The arctan function actually has a value then. So what gives? That series is BULLSHIT.

I, for a moment, disbelieved Wildberger (I shouldn't have) and decided to prove such a thing. That the series would diverge. I did it on paper, got my Calc 2 notes out. And did it. And it is true.

Is this one of the many flaws with real analysis? How come this is just coming to light? Why is Wildberger the only person to say this? Why is everyone else hiding the fact that real analysis doesn't work?

Here is the video and the part where he says this:
https://youtu.be/Snq7UJT8EWg?t=12m27s

First analysis, then number theory... NOW ALGEBRA.

https://www.youtube.com/watch?v=-Z9XL4B0ROk

Anyone taking an algebra course next semester DROP IT THE FUCK DOWN. Wildberger has you. You won't need the inferior algebra built on top of the already debunked "foundation" that we call "set theory".

This is a thread specifically for discussing the newest and WILDEST addition to Wild Theory.