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Need to refresh your math skills? From basic algebra to calculus and beyond.

khanacademy.org

21–30 of 72 posts

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#21

I used their videos on youtube while taking a linear algebra course last semester when I needed an extra lesson on a particular topic. I highly recommend them. Everything I saw was presented in a clear, well articulated matter that made it much, much easier to understand than just reading something out of a book.

His videos. They were all created by one guy.

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#22
I like the style and I appreciate the idea. In fact, I’ve been working on something in the same direction. So, here are a couple of things that I prefer to do differently. First, these are video lectures but without actual students present. As a result, he is essentially talking to himself. I noticed that this causes him to skip some details that students might be wondering about. I prefer to start with actual lectures and initially put them on the web as pdfs (http://users.marshall.edu/~saveliev/Teaching/Fall09/m430/upd...). Then I transcribe them to an online version (http://inperc.com/wiki/index.php?title=Introductory_algebrai...). This is the second problem I have with his approach. Video just isn’t enough. I don’t’ have to explain to you what video doesn’t have and html does: searchability, cross-linking, speed of download, the ability to read and work at your own pace, etc. Certainly, my way is much slower.

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#23

Earlier quoted context omitted.

At school, usually the vast majority of people is interested in games. Of course you can never satisfy everyone, but that's not a good reason IMO to not do anything just because a few people might not like it.

> At school, usually the vast majority of people is interested in games. "People" or "boys" ?? I'd be interested to know your basis for your assertion, and now that the question has been raised I'll start taking informal polls as I go out and give talks. I do about 90 talks a year, and I'll see what the feedback is. And in what aspect of games? Being interested in playing various games is not the same as caring how t…

Everything here is spot on. Most branches of mathematics do not apply directly to games in the same sense that they apply to sciences, financial analysis and other real-life examples.

Games may occasionally be mentioned in passing when applicable, such as using traditional games as examples of probability or the importance of linear algebra and trigonometry in video games.

The problem is that the mathematics used in video games aren't introductory. You need to know a lot about these foundations before you can get very far. Chances are, if you are studying them at such a level, you know what role they play.

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#24
For most people, they come out of high school not just poor at math, they come out "Math Broken" as one of my friends puts it. The second you mention anything to do with Math, their eyes glaze over and their brain completely disengages. I think there are a lot of things that contribute to that, but generally Math is not taught in a very approachable way. The KhanAcademy is I think a very good start in solving that problem.

I came across this site through an article that was on HN sometime last year, around November or December IIRC. Since then I've watched roughly 100 videos on that site. Some of the Finance videos, Trig, and Pre-algebra as a refresher, and I'm now roughly 60 videos into the Linear Algebra videos. Even though I'm in the midst of my master's program now, I've set a goal to watch 2 video's every day as time permits.

I am so impressed with this site, and with Salman Khan. The math is very well done, but it's also very approachable. Most of the videos are roughly 10-15 minutes in length and are highly topical. That makes it easy to jump in and pick up a refresher on something you haven't seen for a while. It's also great for getting into something you haven't ever seen before. Personally I haven't ever had Linear Algebra before, and if you've looked at many of the textbooks, they are pretty dense, particularly if you are self learning. I've found this site to be a great resource in getting oriented and it has really helped me get some traction.

I have recommended this site to dozens of people, and while most of them don't share my love of mathematics, they have been able to get some traction in various problems by using this site as a supplement.

Anyway, as a daily user of the KhanAcademy, I can't say enough good things about the site. I don't think it's a stretch to say it has the potential to revolutionize how math is taught.

The one downside to the site I've noticed is the lack of problems sets. There is a tester that will walk you up through the different topics, but unlike the video's you can't just start where you feel you need to, you have to work up through the early material, and that's fairly time consuming. I have a number of other resource's I'm using for problem sets, but it would be nice to have a few problems to work through for each video.

Overall an absolutely fantastic resource. Rating: 10/10

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#25

Buying good textbooks to learn from is a lot more cost effective than spending on the high-speed internet connections that is needed to download even a short video in any reasonable time. This "resource" is only useful to already have high-speed internet access.

A month of high speed internet is cheaper than a single text book in many countries. Considering there's probably 40 textbooks worth of material on this one page alone, nevermind the rest of the internet, I'd say priorities should be on providing internet access.

That and high-speed internet may be a sunk cost anyway.

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#27
post #24

For most people, they come out of high school not just poor at math, they come out "Math Broken" as one of my friends puts it. The second you mention anything to do with Math, their eyes glaze over and their brain completely disengages. I think there are a lot of things that contribute to that, but generally Math is not taught in a very approachable way. The KhanAcademy is I think a very good start in solving that pr…

I agree with everyone else that it's a fantastic resource and the material is brilliantly presented, but I don't think it will help with the "Math Broken." I'm absolutely not knocking the resource or the site, I can't say enough good things about it, but if someone is already glazed over at the very mention of math, I don't think the videos here will help.

If you think otherwise then I'd really appreciate a suggestion, as I have someone I'd like to point at it ...

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#29
post #24

For most people, they come out of high school not just poor at math, they come out "Math Broken" as one of my friends puts it. The second you mention anything to do with Math, their eyes glaze over and their brain completely disengages. I think there are a lot of things that contribute to that, but generally Math is not taught in a very approachable way. The KhanAcademy is I think a very good start in solving that pr…

I agree with everyone else that it's a fantastic resource and the material is brilliantly presented, but I don't think it will help with the "Math Broken." I'm absolutely not knocking the resource or the site, I can't say enough good things about it, but if someone is already glazed over at the very mention of math, I don't think the videos here will help. If you think otherwise then I'd really appreciate a suggestio…

I agree, I don't think it's the panacea for that problem. It's a start though. The toughest things to get over imo, are the meme's that people will never use math and/or that math is not useful in the real world. The KhanAcademy handles the problem of insecurity about math and a gentler introduction to the topics once someone is interested enough to consider learning it. How you instill that initial desire and overcome their deep seated biases and insecurities about it are a much harder problem.

Re: Need to refresh your math skills? From basic algebra to calculus and beyond.

#30

Buying good textbooks to learn from is a lot more cost effective than spending on the high-speed internet connections that is needed to download even a short video in any reasonable time. This "resource" is only useful to already have high-speed internet access.

Internet access can be pooled, and many people who don't have it at home can get it from libraries, schools, or other organizations. (The same is true of books, of course.)
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