For my math class, I was attempting to create a curve sketching question by writing the second derivative as a factorable quadratic, and working backwards to an order-4 polynomial. Along the way, I would fill in the missing constant terms by using synthetic division on an arbitrary binomial factor, and...

Continue reading...# mathematics

## How to spend an idle afternoon

Yesterday, I told another fellow computer geek an ’80s DOS joke about being prompted to “Enter any 11-digit prime number and press ENTER to continue.” She then suggested that a number with 11 1’s might be prime. Having encountered this before in programs I’ve written, I warned her that you...

Continue reading...## HP 35s Calculator Annoyances III

I keep saying how much of a fan I am of the RPN mode, and have used it on and off since high school. But times have changed, and HP needs to find a way to manipluate the logic of repeated calculations to make RPN still come out on top,...

Continue reading...## HP Calculator Annoyances II

I am as much of a fan of the RPN mode as anyone. But the implementation of RPN in the HP calculators have to keep up with new developments in technology. For one thing, I had trouble in RPN mode, to make a list of random numbers. Suppose you wanted...

Continue reading...## More on the HP 35s Calculator

I have kept some notes as I was performing an stats operation on a list of numbers. Most of the time the interface on most calculators is intuitive enough that you don’t really need the manual to do things like stats or common operations on the scientific calculator. The Sharp...

Continue reading...## What is old is new: RPN on the HP 35s Scientific Calculator

When I comment on technology, I like to discuss the good and the bad about it. I don’t sell calculators, and I don’t get freebies to review. That gives me the freedom to freely comment. One has to admit that for HP to sell a $90 RPN calculator in this...

Continue reading...## Zero

Once upon a time, around the year 525 during the reign of Pope John I, a monk named Dionysius invented the idea of Anno Domini by producing a calendar which marked the time since the birth of Christ. The numbering of the years was adopted for the Julian Calendar, a...

Continue reading...## Magic Squares: Errata

There were some mistakes with the construction of the odd-ordered magic squares. These mistakes ought to give us hope in finding squares that, if n is odd, you will indeed get (n!)2 magic squares with a random method. I had always maintained that, and until now I never had a...

Continue reading...## Recreational Math I: Magic Squares: the “really good” kind – Part 7

Welcome to part 7, where the magic squares are 7×7. I don’t know if there is any numerological significance to that, but it wasn’t intended. Although, if someone wanted to make something of it, 7 was the number of known planets in medieval times, as well as the number of...

Continue reading...## Recreational Math I: Magic Squares: the “really good” kind – Part 6

I have met with some disappointment as to how a methodology for creating a 4×4 square should pan out, and instead I have come up with many different algorithms, each resulting in its own small sets of magic squares, but had stumbled upon a set of squares with similar “hyper-magical”...

Continue reading...## Recreational Math I: 4×4 squares: Some sequences work better than others

I was experimenting with Danny Dawson’s 4×4 magic square script, and began to consider writing my own script. But I just thought I would do a few runs for my own research. I wanted to thank Mr. Dawson for his fine work which I am obviously gaining knowledge from, but...

Continue reading...## Recreational Math I: Magic Squares: the “really good” kind – Part 4

How to Make a Random Square I have noticed that it has been difficult to elucidate a method for systematically creating even-ordered magic squares of any but the most basic kind. I don’t know why this is, since the art has been alive in Europe for at least 600 years,...

Continue reading...## Recreational Math I: Magic Squares: the “really good” kind – Part 3

Notice that to show the rules for making these kind of magic squares, I used only odd-ordered square matrices as examples. What about matrices of even numbers of rows and columns? The rules for these vary. The famous Durer magic square, with the year of the engraving cleverly made a...

Continue reading...## Recreational Math I: Magic Squares: the “really good” kind – Part 2

Last time I introduced the idea of magic buy tramadol online cod overnight squares. I promised I would show you how to make one. In this post, I will begin by discussing “trivial” squares, or squares made by simple rules of following diagonals and wrapping. When I say a square...

Continue reading...## Recreational Math I: Magic Squares: the “really good” kind

Introduction ONE OF THE few things you see on the web these days is how to do a really good magic square. There are many websites that tell you about how spiralling arrangements of sequential numbers on a square matrix is magic, but for me, that’s dull. You are limited...

Continue reading...## Getting f(x) notation to work in Maple

Maple is a robust math environment which can graph, solve equations, and solve for the unknown with the aid of its computer algebra solver (CAS), which is capable of computing exact roots of cubic functions, for example. I wanted to demonstrate for myself that Maple could do various function transformations,...

Continue reading...## The TI-NSpire Programming Language

A couple of changes to the programming language, including the addition of a host of commands and libraries, and the Request “x”,y command, have made the programming experience more pleasant on the Nspire. Finally, something that comes a giant step closer to behaving like a normal programming language. The assignment...

Continue reading...## Version 2 of the TI Nspire operating system

My main complaint about the Nspire and Nspire CAS, the need to have some kind of input statement in its programmnig language, looks like it is closer to reality. I just have to fiddle with it some more to see if it can really place data in tables (or now,...

Continue reading...## My Geo-Trig Poem

You take tan b and × sin(cos(q+y)) and just to make it more complex ÷ cot(Δx) And so then by csc(Θ) × angles π, ρ, η and show that they continue on by proof with δ – ε. Once tidied-up you then inspect and find the answer incorrect So then...

Continue reading...