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No bullshit guide to math and physics

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Re: No bullshit guide to math and physics

#141

Post by ivansavz »

madhadron wrote: post #48

I hesitated to post this, since I think clearer, shorter, better written textbooks are an admirable goal, and I keep a (short) list of good text books I have found over the years. But based on the preview on the website, I'm going to keep referring those who ask me to Gelfand's wonderful basic math texts instead (Algebra, Method of Coordinates, Functions and Their Graphs, Trigonometry -- anyone who wants further poin…

> Gelfand's wonderful basic math texts instead

This is good stuff. Thanks for the pointer. http://www.amazon.com/Algebra-Israel-M-Gelfand/dp/0817636773 http://www.amazon.com/Trigonometry-Gelfand-Mathematical-Semi...

> I haven't seen the physics sections

You should take a look ;) Check out the "Free tutorial" in particular. It is just 7 pages and you can print.

Re: No bullshit guide to math and physics

#142

Post by ivansavz »

anonymouz wrote: post #108
madhadron wrote: post #48

I hesitated to post this, since I think clearer, shorter, better written textbooks are an admirable goal, and I keep a (short) list of good text books I have found over the years. But based on the preview on the website, I'm going to keep referring those who ask me to Gelfand's wonderful basic math texts instead (Algebra, Method of Coordinates, Functions and Their Graphs, Trigonometry -- anyone who wants further poin…

Indeed, stating that these objects result from some classification of all number-like objects seems misleading at best: Most mathematicians would, just as one example, certainly consider p-adic numbers as number like objects. It would be better to point out what really matters in the hierarchy N, Z, Q, R, C: Everybody will accept that N is an interesting object for counting. Z is the quotient group of N under additio…

> vague statements and half-truths

Ouch! A bit offhand no?

My choice was to cover N,Z,Q operationally -- as in what you can do with them. Everyone knows about +,-,/ and so I think it makes sense to connect with this previous knowledge of the reader rather than get into the formality of sets and set containment. I stand by my choice.

Re: No bullshit guide to math and physics

#143

Post by ivansavz »

shuaib wrote: post #98
ivansavz wrote: post #96

Earlier quoted context omitted.

I totally agree with you. I am definitely going to do a cleaned up version with less attitude. I will start by cleaning up the examples. The theory sections are mostly OK. Please send me an email so I can keep you updated on that front.

I hope you are going to keep the cleaned up version separate. Some of us (me at least) would like the book in current form. :)

Oh for sure ;)

For v4.0 of the book, I am thinking of making it customizable. Before you order the book, you will be able to adjust the level of "attitude" with a slider.

Re: No bullshit guide to math and physics

#144

Post by ivansavz »

ntaylor wrote: post #123
ivansavz wrote: post #121

Author here. Some comments before I go catch up on sleep. 1/ The response by the community was amazing. You guys are great! Especially the ones who are nitpicking and fact checking me! I love it. http://cnd.mcgill.ca/~ivan/miniref/HN_wave_Jan1_Jan2.png 2/ By popular demand, I created a PDF version of the book -- mostly changed the font and added more space on each page. Preview is here: http://cnd.mcgill.ca/~ivan/min…

@ivan_ah I just placed an order for a print copy, am I also entitled to a PDF version?

I am looking into how to bundle the two, but it isn't obvious since I use lulu.com for the print version and gumroad for the PDF.

If you send me a proof of purchase of the print version (screenshot of lulu receipt that shows your email), I would be glad to send you the PDF.

Re: No bullshit guide to math and physics

#145

Post by ivansavz »

edgeman27 wrote: post #129

I don't think that there is a need for the liberal use of swearing in a mathematics book ("shit" appears 5 times in your sample PDF alone, two of which are in the title). In my opinion, it makes it sound very amateur and unprofessional. > "Check this shit out:" Could be "Consider this example:" > Now get ready for some crazy shit. Using your... Now for something even more interesting. Using your...

> that there is a need for the liberal use of swearing in a mathematics book

You are right that there is no //need//, but I find that a little swearing goes a long way to make the student who is scared of the subject feel more comfortable. "This is not a math book", they will think -- this is informal narrative like a blog post.

A cleaned up version is in the works. ETA March because I have to finish Linear Algebra and E&M first.

Re: No bullshit guide to math and physics

#146

Post by Dove »

crntaylor wrote: post #137
Dove wrote: post #133

Earlier quoted context omitted.

Yes, and it's pretty easy to prove. Multiplying any rational number by the inverse of another gives you a new rational number. (Zero doesn't have an inverse). A rational number is a number that can be represented as one integer divided by another. Take two rational numbers, A = a/b, and B = c/d. If B has an inverse, then A/B = a/b * d/c = ad/bc. ad and bc are both integers, so A/B is rational.

My point was that you can only divide one rational by another to produce a new rational if the denominator is nonzero . This is not what it says in the book, so there's potential for a newbie to get confused (and anyone reading the book in order to learn from it is, by definition, a newbie).

Oh, then that seems like a pretty pedantic worry. You can't divide by zero in any context; even children know that. It's such an obvious exception that it didn't even occur to me that's what you thought was wrong with the statement.

Re: No bullshit guide to math and physics

#147

Post by lsllc »

ivansavz wrote: post #144
ntaylor wrote: post #123

Earlier quoted context omitted.

@ivan_ah I just placed an order for a print copy, am I also entitled to a PDF version?

I am looking into how to bundle the two, but it isn't obvious since I use lulu.com for the print version and gumroad for the PDF. If you send me a proof of purchase of the print version (screenshot of lulu receipt that shows your email), I would be glad to send you the PDF.

Fantastic, I'll send you an email. Thanks!

Re: No bullshit guide to math and physics

#148

Post by [deleted] »

bane wrote: post #122
chris_wot wrote: post #120

Earlier quoted context omitted.

\in?

\in means "in the set of" Given the definition "The definition of a rational number is a number that can be expressed as the quotient of two integers where the denominator is not 0." Let N be the set of all integers and Q be the set of all rational numbers. Trivially 0 is in the set N, 5 is in the set N by the definition 0/5 is in Q. Therefore 0 is in Q. QED.

[deleted]

Re: No bullshit guide to math and physics

#149

Post by chris_wot »

bane wrote: post #122
chris_wot wrote: post #120

Earlier quoted context omitted.

\in?

\in means "in the set of" Given the definition "The definition of a rational number is a number that can be expressed as the quotient of two integers where the denominator is not 0." Let N be the set of all integers and Q be the set of all rational numbers. Trivially 0 is in the set N, 5 is in the set N by the definition 0/5 is in Q. Therefore 0 is in Q. QED.

Ah, I see! Deleted my old comment. Nice :-)
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