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Math Academy, part 1: My eigenvector embarassment

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Re: Math Academy, part 1: My eigenvector embarassment

#11

Post by beezle »

aithrowawaycomm wrote: post #9
i2go wrote: post #3

he was a physics and math major and did not know eigenvectors and eigenvalues? i would like to know how is this possible. can someone explain it to me?

He is a bit older. Linear algebra is also very old, but it didn't really become the field we know today until the 1950s. I would add that in 2025 it is cheap to buy a computer that can solve large linear systems, but that certainly wasn't true in 1975, so linear algebra was less applicable in the real world. I am not too familiar with the pedagogical history of linear algebra, but I've been reading some advanced unde…

I was a double major, one in physics, in the 80s. After the three semester engineering physics classes, intro QM was taught spring sophomore year. We used Liboff. In addition, it was required for all physics, chem and engineering majors to take math 20(5?) which was linear algebra.

And given that most of basic QM was formalized by 1930 and relies upon eigenvectors, hard to see any physics course taught since that time not having it.

Re: Math Academy, part 1: My eigenvector embarassment

#12

Post by raincole »

insane_dreamer wrote: post #7

is MathAcademy that much better that KhanAcademy (which also has a Linear Algebra course and covers eigenvalues of course), which is free? Considering it for my youngest kids, but my eldest (now finished college with a degree in engineering) used Kahn Academy as a high school supplement and it was quite good (this was about 10 years ago). (She didn't take the KahnAc LinAlg course -- not sure it was around at that tim…

Math Academy has some "gamification" (using this term loosely) to push you to do your homework. That's actually great if you care about learning efficiently.

But as far as I remember, it hardly teaches you how to write proofs, so how much it actually teaches math is a bit questionable.

Re: Math Academy, part 1: My eigenvector embarassment

#13

Post by rubing »

eigenvectors were the only tough part of the linear algebra course i took, i think that's b/c it's quite a bit to learn before you start seeing the point of it. methods like PCA are rely heavily on eigendecompositon and allow you to reduce the dimensions of data...this is useful in all sorts of ways like compression for instance (e.g. getting rid of the dimensions that aren't very meaningful).

Re: Math Academy, part 1: My eigenvector embarassment

#14

Post by [deleted] »

aithrowawaycomm wrote: post #9
i2go wrote: post #3

he was a physics and math major and did not know eigenvectors and eigenvalues? i would like to know how is this possible. can someone explain it to me?

He is a bit older. Linear algebra is also very old, but it didn't really become the field we know today until the 1950s. I would add that in 2025 it is cheap to buy a computer that can solve large linear systems, but that certainly wasn't true in 1975, so linear algebra was less applicable in the real world. I am not too familiar with the pedagogical history of linear algebra, but I've been reading some advanced unde…

[deleted]

Re: Math Academy, part 1: My eigenvector embarassment

#15

Post by cultofmetatron »

insane_dreamer wrote: post #7

is MathAcademy that much better that KhanAcademy (which also has a Linear Algebra course and covers eigenvalues of course), which is free? Considering it for my youngest kids, but my eldest (now finished college with a degree in engineering) used Kahn Academy as a high school supplement and it was quite good (this was about 10 years ago). (She didn't take the KahnAc LinAlg course -- not sure it was around at that tim…

> is MathAcademy that much better that KhanAcademy

I'm using mathacademy and I will unequivocally say its better and worth the money. First it uses a assessment to test your knowledge and will send you modules to fill in the gaps. I finished foundations 1 and now I'm in the middle of foundations 2.

One thing I love about math academy is that you spend very little time reading and no time watching videos on the subject. You get a short walkthrough of how to solve a problem and then it gives you a few more problems building up the complexity. A few days later it gives you the problems again to test your knowlege. the interface is not as pretty as khan academy but you're basically learning by doing and its very effective. I wish it was around when I was in university.

Re: Math Academy, part 1: My eigenvector embarassment

#16

Post by shireboy »

insane_dreamer wrote: post #7

is MathAcademy that much better that KhanAcademy (which also has a Linear Algebra course and covers eigenvalues of course), which is free? Considering it for my youngest kids, but my eldest (now finished college with a degree in engineering) used Kahn Academy as a high school supplement and it was quite good (this was about 10 years ago). (She didn't take the KahnAc LinAlg course -- not sure it was around at that tim…

We homeschool our son and after a lot of trouble with an online course that used Saxon math, we landed on Math Academy. I found it much easier to use than Khan both for the parent and student. I do sometimes wish there was video content and discussion of application. But my son does it first thing every weekday and really seems to do good with it. Also worth noting it is accredited and lets you print a transcript.

Re: Math Academy, part 1: My eigenvector embarassment

#17

Post by emseetech »

insane_dreamer wrote: post #7

is MathAcademy that much better that KhanAcademy (which also has a Linear Algebra course and covers eigenvalues of course), which is free? Considering it for my youngest kids, but my eldest (now finished college with a degree in engineering) used Kahn Academy as a high school supplement and it was quite good (this was about 10 years ago). (She didn't take the KahnAc LinAlg course -- not sure it was around at that tim…

Much better for anyone so motivated. There's considerably less handholding, the questions are a little "trickier" (without being unnecessarily cruel) and there's a more intense pacing to it since there's no videos. It's focused on learning-by-doing, which I love.

For many, I would recommend Khan Academy. It's a great resource, especially since it's free. But if learning math is about more than just passing a class, Math Academy is worth every penny.

Re: Math Academy, part 1: My eigenvector embarassment

#18

Post by HPMOR »

cultofmetatron wrote: post #15
insane_dreamer wrote: post #7

is MathAcademy that much better that KhanAcademy (which also has a Linear Algebra course and covers eigenvalues of course), which is free? Considering it for my youngest kids, but my eldest (now finished college with a degree in engineering) used Kahn Academy as a high school supplement and it was quite good (this was about 10 years ago). (She didn't take the KahnAc LinAlg course -- not sure it was around at that tim…

> is MathAcademy that much better that KhanAcademy I'm using mathacademy and I will unequivocally say its better and worth the money. First it uses a assessment to test your knowledge and will send you modules to fill in the gaps. I finished foundations 1 and now I'm in the middle of foundations 2. One thing I love about math academy is that you spend very little time reading and no time watching videos on the subjec…

MathAcademy really is fantastic. I've done 5300 xp so far (80+ hours), and am almost finished with their Math for Machine Learning. It's remediated a lot of things I've struggled with during my University ML classes. Seriously a wonderful pedagogical experience. I can integrate multivariate functions easily, know all my derivative trig identities, and I don't get confused by continuous random variables any more.

Re: Math Academy, part 1: My eigenvector embarassment

#19

Post by emseetech »

HPMOR wrote: post #18
cultofmetatron wrote: post #15

Earlier quoted context omitted.

> is MathAcademy that much better that KhanAcademy I'm using mathacademy and I will unequivocally say its better and worth the money. First it uses a assessment to test your knowledge and will send you modules to fill in the gaps. I finished foundations 1 and now I'm in the middle of foundations 2. One thing I love about math academy is that you spend very little time reading and no time watching videos on the subjec…

MathAcademy really is fantastic. I've done 5300 xp so far (80+ hours), and am almost finished with their Math for Machine Learning. It's remediated a lot of things I've struggled with during my University ML classes. Seriously a wonderful pedagogical experience. I can integrate multivariate functions easily, know all my derivative trig identities, and I don't get confused by continuous random variables any more.

I'm working through Foundations specifically to do Math for Machine Learning and I'm very excited for that course. What were your thoughts on it?

Also, if they ever did a Math for Computer Graphics course I'd never cancel my subscription.

Re: Math Academy, part 1: My eigenvector embarassment

#20

Post by emseetech »

raincole wrote: post #12
insane_dreamer wrote: post #7

is MathAcademy that much better that KhanAcademy (which also has a Linear Algebra course and covers eigenvalues of course), which is free? Considering it for my youngest kids, but my eldest (now finished college with a degree in engineering) used Kahn Academy as a high school supplement and it was quite good (this was about 10 years ago). (She didn't take the KahnAc LinAlg course -- not sure it was around at that tim…

Math Academy has some "gamification" (using this term loosely) to push you to do your homework. That's actually great if you care about learning efficiently. But as far as I remember, it hardly teaches you how to write proofs, so how much it actually teaches math is a bit questionable.

| it hardly teaches you how to write proofs

Proofs are coming, the site is a work in progress.

https://x.com/justinskycak/status/1835085776524394951

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