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Math notes to take you from one year of college calculus to grad student level

math.ucr.edu

21–30 of 70 posts

Re: Math notes to take you from one year of college calculus to grad student level

#21
post #4

I found the writing style to be incredibly obnoxious and hand wavy, and really make me stop reading.

Example: It is time to note that our one-parameter symmetries are groups in the sense of modern algebra. Why? To masturbate with nomenclature as you do in an abstract algebra class? No.

Re: Math notes to take you from one year of college calculus to grad student level

#22
I guess this is a good a time as any to show the organic chemistry notes that I've been writing up.

https://github.com/alexganose/chem1201

So far I've done my first year notes. They aren't particularly organised, they are literally just latex versions of my handwritten notes so they won't be good to learn from, however as a summary they are quite useful.

I'm doing it for purely selfish means as I can revise from these notes better, but I thought it would be good to open source them so people can use them if they want.

Re: Math notes to take you from one year of college calculus to grad student level

#23
post #4

I found the writing style to be incredibly obnoxious and hand wavy, and really make me stop reading.

That's interesting. I guess 'obnoxious' is pretty subjective, but which part did you find 'hand-wavy'? The parts I've read have been quite rigorous.

I don't think hand wavy was exactly the right way to describe it, more like flippant.

Re: Math notes to take you from one year of college calculus to grad student level

#24
post #4

I found the writing style to be incredibly obnoxious and hand wavy, and really make me stop reading.

That's interesting. I guess 'obnoxious' is pretty subjective, but which part did you find 'hand-wavy'? The parts I've read have been quite rigorous.

Also, some examples of what I found objectionable:

* Abstract algebra, topology (local and global) folds into a useful, intuitive toolset for ordinary differential equations and partial differential equations, be they linear or nonlinear. (This annoying to read be they construction is used multiple times)

* Abstract algebra, topology, and algebraic topology aren’t vacuous constructs built for useless mental masturbation by “pure” mathematicians; the study of differential equations is more than a study of botany.

Re: Math notes to take you from one year of college calculus to grad student level

#25

From Sentence 5 of Example 1.1: "The symmetry is a smooth (differentiable to all orders) invertible transformation mapping solutions of the ODE to solutions of the ^ODE^. Invertible means the Jacobian is nonzero: x'x y'y - x'y y'x != 0" Yeah, understood about 5% of that.

Here's how I broke it down, it has been a little while since I've been in a math class * Differentiable to all orders means that for each derivation, no cusp will appear in the curve. A cusp means that the next order of derivation will not be defined at that point on the curve.

* 'The symmetry is a smooth invertible transformation mapping solutions of the X to solutions of the Y'. - I now understand that the stuff I just paraphrased means that it's just a mapping, and that it's invertible. - ODE = Ordinary Differential Equation. Cool. Rings a bell. It looks like ^ODE^ is just the next order of derivation? And this mapping, the symmetry, is just describing how the next order of derivation relates to the first (I think, that is not exactly clear in the time I spent).

* Invertible means the Jacobian is nonzero... Describing to a sophomore that a mapping is invertible in these terms is pretty vague (this section is supposed to be accesible to sophomores). The Jacobian is the determinant of a particular form of matrix, http://mathworld.wolfram.com/Jacobian.html

So aside from that last bit it came apart okay. I have noticed that when you have completed a certain amount of math (or any topic) it is hard to exclude certain bits or to describe things in a simpler fashion

Re: Math notes to take you from one year of college calculus to grad student level

#27
This plus MIT OpenCourseware & Coursera could really teach someone physics. And I mean real physics not pop culture physics. IE breaking the fundamental laws of thermodynamics and having a negative temperature(the conclusion drawn by the website doesn't fit the actual paper).

Re: Math notes to take you from one year of college calculus to grad student level

#28
I'm surprised by the excitement at every piece of teaching material or set of course notes posted here. Free textbooks and PDF notes have been around for years, especially for mathematical topics.

This PDF won't do the work for you, and you can't skim-read this kind of material. To properly understand an area of mathematics then you need to put a significant amount of time and effort into working through the text, and a set of condensed notes is probably not as good as a well written textbook with careful examples and exercises (and with fewer errors).

I'm not making a judgement about the quality of this document, I guess I'm saying that if you really wanted to learn this material you would have started already.

Re: Math notes to take you from one year of college calculus to grad student level

#29
post #4

I found the writing style to be incredibly obnoxious and hand wavy, and really make me stop reading.

iconjack, you are a dead user. Time to create a new account.

What do you mean, a dead user? I was just quoting from the document, as an example of writing some might find obnoxious. Personally I find it rather entertaining.

Re: Math notes to take you from one year of college calculus to grad student level

#30
post #28

I'm surprised by the excitement at every piece of teaching material or set of course notes posted here. Free textbooks and PDF notes have been around for years, especially for mathematical topics. This PDF won't do the work for you, and you can't skim-read this kind of material. To properly understand an area of mathematics then you need to put a significant amount of time and effort into working through the text, an…

>> if you really wanted to learn this material, then you would have started already

This is pretty much the only statement i have an objection or reaction to.

I simply don't understand the basis for assertions along these lines. These sorts of fatalistic proclamations are made not-infrequently in the context of programming and development as well.

Its as if we feel that the only ones worthy of pursuing a given discipline are those who realized their passion and interest early in life. Why the exclusivity? This is just knowledge, after all.

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