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Primary Mathematical Interests:

Study and use of negligible sets, especially involving porosity notions and fractal dimension notions.

Application and refinements of the Baire category method for proving existence.

Classical point set theory and real function theory.

History of nowhere differentiable continuous functions and history of the topics above.

My email address has the form "first-name period last-name at YAHOO period COM".


2d
comment High-level linear algebra book
Also, for freely available texts, try this google search: online math texts "linear algebra"
2d
comment High-level linear algebra book
(continuation) David Lay's linear algebra book, and I thought it was fine too (but it was wordier and filled with more applications from outside of mathematics than the 1970 Kolman book I read around 1975). This 11 January 2009 sci.math post archived at Math Forum might also be helpful.
2d
comment High-level linear algebra book
Most widely used elementary linear algebra texts (published within the same 10 to 20 year period) are really not all that different in my eyes. What I would suggest is to browse the library shelves of a nearby college/university library and see what seems to fit your specific likes and dislikes. That said, I read through Bernard Kolman's linear algebra book on my own in high school (this was the 1970 first edition, which is quite a bit shorter than the later editions) and didn't later regret that I should have used another book, and in 1999-2000 I taught some courses using (continued)
Jan
27
comment The obivious “why”-questions
One of the problems in something like this is trying to pin down exactly what $8+2$ means in a way that makes it at least conceptually distinct from $2+8.$ For example, perhaps $8+2$ means you throw down $8$ coins, then throw down $2$ coins, and then count how many coins are in the pile, whereas $2+8$ would mean you throw down $2$ coins, then throw down $8$ coins, and then count how many coins are in the pile. Of course, you'd probably want a less empirical approach, but at some point you need to answer the question of exactly what $8+2$ and $2+8$ mean besides being different marks on paper.
Jan
27
comment How to calculate the sum of a general series
You can find a lot of methods that don't rely on advanced mathematics (or even calculus, for the most part) in Part 2 of Chrystal's Algebra.
Jan
26
comment Convergence of infinite products
A quick google search for the phrase "infinite products" along with the word "summability" turned up a lot of hits, including this 1929 paper.
Jan
23
comment Construct a set of real numbers whose limit points comprise the set of integers $\mathbb{Z}$
This statement is not true: Another trivial example would be the integers themselves.
Jan
23
comment Lang's Linear Algebra: what's next?
Related math stackexchange questions: What's a good book on advanced linear algebra? and High-level linear algebra book
Jan
22
comment Phenomenon that have $\sqrt{x}$ functions? Grading curve, inverse-square law, etc?
@JackOfAll: The function $v(t) = Ct$ is an increasing function, at least for a nonzero and positive constant $C.$ The graph of this function is a line with slope $C.$
Jan
20
comment Explanation For The Non Existence Of A Limit
One concise way to verbally state the non-existence of a limit is to say that there exists an $\epsilon > 0$ such that, for infinitely many positive integers $N,$ the distance between $x_N$ and $L$ is at least $\epsilon$ (equivalently, is greater than $\epsilon).$ (Thanks to GFauxPas for pointing out an error in the earlier version of this comment.)
Jan
20
revised Utilizing scientific notation: change distance in light years to distance in miles
added 162 characters in body
Jan
20
comment Utilizing scientific notation: change distance in light years to distance in miles
Oops, I used $5.9 \times {10}^9$ (incorrect) instead of $5.9 \times {10}^{12}$ (correct).
Jan
20
revised Utilizing scientific notation: change distance in light years to distance in miles
fixed typo
Jan
20
revised Utilizing scientific notation: change distance in light years to distance in miles
edited title
Jan
20
answered Utilizing scientific notation: change distance in light years to distance in miles
Jan
20
comment Utilizing scientific notation: change distance in light years to distance in miles
I looked through the tags and saw one for "arithemtic", and since this is an arithmetic word problem, I'd go with arithmetic.
Jan
20
comment Utilizing scientific notation: change distance in light years to distance in miles
I don't see the connection to abstract algebra.
Jan
20
comment Phenomenon that have $\sqrt{x}$ functions? Grading curve, inverse-square law, etc?
@JackOfAll: Its speed is linear with time (i.e. $v = Ct$ for some constant $C),$ while the total distance traveled is quadratic with time (i.e. $d = Kt^2$ for some constant $K).$ Indeed, $C$ = $g$ and $K = \frac{1}{2}g,$ where $g$ is the acceleration of gravity.
Jan
20
comment Solving this integral?
@seeker: Wow ... and thanks!
Jan
16
comment How to avoid fractions when writing expressions?
I'd just write them as $x/(\log y)$ and $(a+b+c+d+e+f)/2$ if vertical format couldn't be used.