Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Relearning math as an adult

gmays.com

Post reply on HN
Print view View original

181–190 of 268 posts

Re: Relearning math as an adult

#181

Post by chasd00 »

viraptor wrote: post #129
galaxyLogic wrote: post #93

Earlier quoted context omitted.

I find the concept of "underlying knowledge graph" interesting. What does it mean? I assume it means such a graph connects the topics together as "pre-requisites". To understand A you need to already understand B and C, and to understand B you need to understand D and ... etc. But the thing about such a graph is that really it must be a tree, not just a directed graph. Why? Because there cannot be cycles in it. If to…

> it must be a tree, not just a directed graph It may be a tree. But it must be a DAG (directed acyclic graph).

Heh knowledge graphs sometimes don’t feel acyclic, at least not to me anyway. Sometimes I’m stuck bouncing back and forth :)

Re: Relearning math as an adult

#182

Post by chasd00 »

boxfire wrote: post #3

I may be biased as I am a trained Mathematician, but I always feel when someone says "Math is Hard", that is because they had bad teachers. Math is easy if you build up from fundamentals, not like physics education where you say "but lets delete everything before because it had an oversimplifying assumption", rather if you build your knowledge entirely sequentially from things you know or assume, you build up a toolb…

One advantage math (and computer science) has is it’s entirely man made. You can start at the beginning and follow every step of the way.

Re: Relearning math as an adult

#183

Post by aleph_minus_one »

gmadsen wrote: post #175
aleph_minus_one wrote: post #159

Earlier quoted context omitted.

> every working mathematician needs to understand at least basic set operations, simple identites like De Morgan's laws (I don't care if you know the name or not), as well as what cartesian products, relations and functions are. This is stuff that you learn in the 5th or 6th grade in school, and is about as far removed from what mathematicians call "set theory" as basic arithmetic operations are from college math cou…

that is a little bit of hyperbole. No school in 5th or 6th grade is giving formal definitions of relations and functions. There is a reason nearly all undergrad math books in analysis, topology, algebra, all devote an entire first chapter to it.

> No school in 5th or 6th grade is giving formal definitions of relations and functions.

I remember that my math teacher pretty surely did.

> There is a reason nearly all undergrad math books in analysis, topology, algebra, all devote an entire first chapter to it.

Indeed there exist multiple good reasons:

- recapitulation

- setting up the notation

- clarifying how the textbook defines the relevant mathematical objects, because the definitions of some concepts might differ depending on the textbook

- making clear what existing standard the textbook expects from the learner

- ...

Re: Relearning math as an adult

#184

Post by felideon »

burrish wrote: post #123

Nice Ad post, there are A LOT of free resources to learn math on the web, why go through $49/month ? People are citing Khan Academy which I warmly recommend, there are a lot of good Math teachers teaching math on YouTube, and there is also OpenStax.org [1] which releases free public books on different subjects including... you guessed it... math ! Go check it out ! But maybe for some people, spending money is a neces…

Do you know how much people pay for tutoring for their kids IRL? You might find a college student willing to charge $25 an hour or whatever, but if you take them to one of those corporate tutoring places you’re looking at $400/mo at minimum.

$50 is a bargain when you have nervous parents whose kids are struggling and Math is hurting their GPA.

Re: Relearning math as an adult

#185

Post by burrish »

felideon wrote: post #184
burrish wrote: post #123

Nice Ad post, there are A LOT of free resources to learn math on the web, why go through $49/month ? People are citing Khan Academy which I warmly recommend, there are a lot of good Math teachers teaching math on YouTube, and there is also OpenStax.org [1] which releases free public books on different subjects including... you guessed it... math ! Go check it out ! But maybe for some people, spending money is a neces…

Do you know how much people pay for tutoring for their kids IRL? You might find a college student willing to charge $25 an hour or whatever, but if you take them to one of those corporate tutoring places you’re looking at $400/mo at minimum. $50 is a bargain when you have nervous parents whose kids are struggling and Math is hurting their GPA.

$0 is a bargain too :)

Re: Relearning math as an adult

#186

Post by pokerface_86 »

hintymad wrote: post #10

It looks how do do proofs is at university level in the US. I wonder why other countries start to teach kids how to do proofs from grade 7. They start with rigorous proofs in Euclidean geometry, the move to solid geometry, then to proofs in elementary functions, sets, number theories, and etc, then to polynomials and simple discrete maths and analytic geometry. By the time a kid graduates high school. using things li…

[dead]

Re: Relearning math as an adult

#187

Post by jacquesm »

eps wrote: post #133
jacquesm wrote: post #49

Earlier quoted context omitted.

Why am I not surprised that a marketeer shows up in an 'organic' posting about a company.

Don't be nasty. Especially ridiculing a tech person giving detailed and interesting answers as a "marketeer".

"Director of Analytics"

Re: Relearning math as an adult

#188

Post by jacquesm »

nextlevelwizard wrote: post #107
jacquesm wrote: post #104

Earlier quoted context omitted.

I wrote "I had excellent teachers", not that they were super good at math.

you also wrote other stuff.........

Which I still stand by. Math is easy for people that are good at math, computer programming is easy for people that are good at programming etc. For the rest of the world those things are not so easy, even if they do have good teachers. To assume that everybody can be equally good at math or computer programming is denying reality. I am a pretty good teacher and have found that some kids take to this stuff like fish to water and for others it is a serious effort with everything else being more or less constant. It would be great if we could identify that one single factor of 'the teacher' as the root cause of all of the trouble but unfortunately that's an oversimplification. Sure, there are bad teachers, and some of those are really good at math themselves. But that's just a fraction of the problem.

Re: Relearning math as an adult

#189

Post by mebassett »

baq wrote: post #128
hiAndrewQuinn wrote: post #119

About a year ago my wife and I made the joint decision to get her into college for a bachelor's degree in either English or computer science. Here in Finland, university admissions are based around how well you did on various end of school exams, and she fortunately did quite well on all of them a decade ago - except for math. She bombed math due to health and family problems as a teenager decimating her ability to p…

> set her nose to the grindstone Worth calling out the key observation: it takes practice, and lots of it (for most people, anyway) to get good at math. Just reading about it does zilch.

yes. learning to doing maths is a bit like learning to play an instrument in that you have to spend lots of times practicing scales or other simple stuff (doing the exercises) before you can really be creative on it.

or like learning to write - you got to spend lots of time practicing and memorizing your letters before you can start getting to words and sentences and novels.

Re: Relearning math as an adult

#190

Post by koromak »

Always wanted to try this, but I've got a hangover from my highschool days. I was bad at math, or it was taught very badly, or both. I'm worried I'd need to start from zero, like Algebra 1 and Geometry
Post reply on HN