Math Forum / Mathematics / Recreational Math / August 2006

Here are two websites offering good HP-16C emulators ("+" = a
positive, "-" = a negative, "*" = a comment).
www.hp16.com, Chris Lusko, Java applet and application
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2b[ 40- {2(a+b) + 5(a -b)}]
= 5a - a - b/2
How was the solution arrived at. Step by step explaination please.

Yesterday, out of the blue, while painfully trying to resolve
this vital question of modern times, about the women, - I had
a flash of bright, revelation-like insight!
My bold hypothesis is here to discuss:

I don't know much about number theory, but I do enjoy playing with
numbers. I just stumbled on this curious little theorem and I assume it
is already well known, but just in case it's not, here goes:
It is well known that if P is prime then b^(P-1) mod P = 1, but what

Hello all the computer algebra fans,
None of Maple versions can calculate this integral.
int(exp(-z^2)*exp(-z)*sin(z)/z, z= 0..infinity);
Is there a lady or a gentleman who can show a step-by-step

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1. Reasonably good initial design ideas.
2. Lousy (human driven) quality assurance.
3. Attempts to extend the system.

I am trying to find out the way to calculate the following problem: If a cilinder of a given size is filled up by particle suspension in a homogenous way, what portion of the particles will come in contact with the cilinder wall?

Hello the computer algebra adorers,
Neither Mathematica nor Maple can calculate this integral
straightforwardly.
Is there a person who can show how to get to the exact value

My 145th weekly math puzzle is about quartering a circle. However, there are
some restrictions to be applied, in order to avoid this from being too easy
a task.
Please be invited to visit http://home.planet.nl/~p.j.hendriks/ppvdw.htm and

Hello the Maple fandom,
None of the Maple versions since at least 1994 on can get
this integral correctly.
Is there a Maple soul who can show how to get to the exact

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Typical modern computer algebra system
http://universe-review.ca/I10-28-cuttlefish.jpg
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find all matrices commuting with A.
A={{1.1},{0.1}}
or how can i solve that kind of "problems"?
Blaz

A 2-dimensional plane contains every snake in this puzzle, of which there
are at least one. You may think of a snake as a curve with one end called
the snout, one end called the tail, and the rest called the middle. Snakes
can't overlap or cross each other, because, you know, ...

Starting with a blank Sudoku board, players alternately place numbers
in the grid, subject only to the restriction that the number placed
must not violate the standard Sudoku rules. The object is not to
complete the Sudoku grid, but to force your oponent into a situation

Can anyone please help me with the following problem? I've been wrecking
my brain for the last few days trying to figure this out and I haven't
been able to do so. I need a formula that given the a pair of numbers
produces the following results.