Live data from Hacker News

Ask HN: How to self-learn math?

news.ycombinator.com

161–170 of 215 posts

Re: Ask HN: How to self-learn math?

#161
Probably not a perfect book for someone at the HS level, but just a bit past that I would HIGHLY recommend MacLane’s Mathematics Form and Function.

It’s a revisionist history of mathematics aimed to demonstrate how ideas flow from one to another. He eliminates a lot of dead-ends and takes a perspective as to one “ought” to move from one subject or discovery to another. OTOH, the historical perspective is both readable and often a missing piece which makes other math tougher.

Re: Ask HN: How to self-learn math?

#162
post #150

Earlier quoted context omitted.

Depends what your goal is. I cant imagine anything worse than High School style teaching of mathematics. Its awful. That repetitive calculation, entirely unnecessary for almost any real world situation. Almost every time you are doing repetitive calculation what you should have been taught was a second or third conceptualisation of whatever maths you are looking at. So linear algebra I was only ever taught numericall…

My high school calculus and physics teachers synchronized their classes, so shortly after we learned something in calculus, we would use it in physics. Since then I’ve learned this is not as common as it should be! Perhaps it works especially well in that case because calculus was literally invented to do the kind of physics you learn in high school, so it’s a very natural combination. Linear algebra (e.g.) is so gen…

My high school only taught physics without calculus. In 12th grade when I took calculus separately I was sort of annoyed to realize how much easier physics would have been using calculus.

Re: Ask HN: How to self-learn math?

#163

>My current proficiency level is pre-high school mathematics as I didn't pay much attention in high school, learning effectively nothing. Advice from someone who was in the same position: Take a class. Multiple classes. Go sign up for a Mathematics AS at your nearest community college right now. You will never know enough of what you don't know to learn this stuff on your own. A lot of it is just doing the painful re…

Depends what your goal is. I cant imagine anything worse than High School style teaching of mathematics. Its awful. That repetitive calculation, entirely unnecessary for almost any real world situation. Almost every time you are doing repetitive calculation what you should have been taught was a second or third conceptualisation of whatever maths you are looking at. So linear algebra I was only ever taught numericall…

It's always a good idea to anchor new knowledge to pre-existing knowledge. (Perhaps this could be called coral reef learning?)

Adult brains, with less plasticity, are able to synthesise new concepts that build on what they already know.

Re: Ask HN: How to self-learn math?

#164
Jeremy Kun (who is worth reading beyond this article) has a post with very useful insights:

https://j2kun.svbtle.com/mathematicians-are-chronically-lost...

It begins (and there is far more of value in the post):

Many people who are in this position, trying to learn mathematics on their own, have roughly two approaches. The first is to learn only the things that you need for the applications you’re interested in. There’s nothing wrong with it, but it’s akin to learning just enough vocabulary to fill out your tax forms. It’s often too specialized to give you a good understanding of how to apply the key ideas elsewhere. A common example is learning very specific linear algebra facts in order to understand a particular machine learning algorithm. It’s a commendable effort and undoubtedly useful, but in my experience this route makes you start from scratch in every new application.

The second approach is to try to understand everything so thoroughly as to become a part of it. In technical terms, they try to grok mathematics. For example, I often hear of people going through some foundational (and truly good) mathematics textbook forcing themselves to solve every exercise and prove every claim “left for the reader” before moving on.

This is again commendable, but it often results in insurmountable frustrations and quitting before the best part of the subject. And for all one’s desire to grok mathematics, mathematicians don’t work like this! The truth is that mathematicians are chronically lost and confused. It’s our natural state of being, and I mean that in a good way. ...

Re: Ask HN: How to self-learn math?

#165
I was in a similar situation a few years back but my weakness was calculus. I really had no grasp of what it was used for until I had to learn as part of my work. I was on the brink of losing my job if I hadn't. I had a very patient boss as mentor who spent hours teaching me the practical applications of it - remotely over phone. Now I love calculus.

So I believe the best way to learn math is by finding areas where you are forced to apply it. And it is never too late. I learnt most of it after turning 30.

Re: Ask HN: How to self-learn math?

#166
post #82

Earlier quoted context omitted.

I find there are things I’m missing. Does the precalculus stuff cover geometry and polynomials?

Precalc basically covers algebra and trigonometry. From my experience as a CompSci major, euclidean geometry is not really necessary.

True, but CompSci isn’t the motivation of this poster.

Re: Ask HN: How to self-learn math?

#168
You can self learn math to a certain point but eventually you will reach a subject where its introductory text requires a context not written plainly. This is easily observable in research. Researchers do not write papers with the goal that everyone understand their work but rather that those in their field understand so the work can be verified. You are then stuck either having to derive the mathematical principles you need or you will have to ask others for help.

Re: Ask HN: How to self-learn math?

#169
post #71

Earlier quoted context omitted.

To the above I would add: How to Think Like a Mathematician - Kevin Houston (an excellent book to read before starting) How to Read and Do Proofs - Solow The Keys to Advanced Mathematics: Recurrent Themes in Abstract Reasoning - Solow Calculus - Spivak (Actually a Real Analysis book, not a Calculus book, see e.g. https://math.stackexchange.com/questions/1811325/spivaks-cal... ) Linear Algebra Done Right - Axler (Inte…

There's also How To Solve It by Polya. Small, accessible, casually written.

That Polya book is very good. [1] [2]

I had read it many years ago. It may be influential beyond what people know. There is a version inspired by it, for programming, called How to Solve it by Computer [3], by R. G. Dromey, who, IIRC, was/is a professor at an Australian university (Wollongong?).

I had the Dromey book. It is not exactly parallel to the Polya book, because it shows the details of how to come up with a solution, either in pseudocode or in a Pascal-like language, while the Polya book, IIRC, is more about principles and techniques for general problem-solving.

[1] https://press.princeton.edu/titles/669.html

[2] https://en.wikipedia.org/wiki/How_to_Solve_It

[3] https://en.wikipedia.org/wiki/How_to_Solve_it_by_Computer

I'm pasting below the first few paragraphs from the URL [1] above:

[ A perennial bestseller by eminent mathematician G. Polya, How to Solve It will show anyone in any field how to think straight. In lucid and appealing prose, Polya reveals how the mathematical method of demonstrating a proof or finding an unknown can be of help in attacking any problem that can be "reasoned" out—from building a bridge to winning a game of anagrams. Generations of readers have relished Polya's deft—indeed, brilliant—instructions on stripping away irrelevancies and going straight to the heart of the problem.

First published in 1945.

George Polya (1887–1985) was one of the most influential mathematicians of the twentieth century. His basic research contributions span complex analysis, mathematical physics, probability theory, geometry, and combinatorics. He was a teacher par excellence who maintained a strong interest in pedagogical matters throughout his long career. Even after his retirement from Stanford University in 1953, he continued to lead an active mathematical life. He taught his final course, on combinatorics, at the age of ninety. John H. Conway is professor emeritus of mathematics at Princeton University. He was awarded the London Mathematical Society's Polya Prize in 1987. Like Polya, he is interested in many branches of mathematics, and in particular, has invented a successor to Polya's notation for crystallographic groups. ]

The John Conway mentioned is the one who invented the Game of Life.

https://en.wikipedia.org/wiki/John_Horton_Conway

https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life

Re: Ask HN: How to self-learn math?

#170

Nothing beats having a (good) teacher. Self-learning, no matter how smart you are, is pitifully slow without a teacher. Half an hour with a good teacher can save you weeks of table head-butting. (But obviously you can't rely only on the teacher.) As for books, it's not a spectator sport: you gotta do it yourself. Read a sentence, then work it out yourself with pen & paper. You can't get it just from reading alone. Fi…

I disagree with the general statement that leaning maths is "pitifully slow without a teacher". So long as one has structure (e.g. some kind of syllabus) and has access to google, then learning can proceed very efficiently indeed. In addition, by being able to work through difficulties independently you can "be your own master" so to speak, earning the confidence to solve new and difficult problems without assistance…

I think for most people though, not having a teacher doesn't mean "pitifully slow", it means they will eventually forfeit the endeavor. The option to self-study has always been there, and now Khan Academy is here too, but I think there's a reason why we haven't seen an education revolution just yet, and I think it's because an interactive teacher who monitors your state and thinks about the road ahead is key.

There are even a lot of math teachers who feel anxiety about basic math. Why don't they simply self-study?

Post reply on HN