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    Twos complement.

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Dates that Read the Same Backwards and Forwards [02/02/2010]

A student sees a palindrome in the date 01 02 2010, and wonders how to generate all such palindromic dates. Building on another math doctor's work with date arithmetic, Doctor Carter shares a program written in C, then goes on to explain the purpose of each line of code.

Decimal To Fraction Conversion - A Simpler Version [11/25/2002]

A simpler version of the algorithm.

Definition of Floating Point Data [07/02/2001]

What are 'floating point data'? How do they differ from an integer? What are some examples?

Determining File Compression Ratio [04/11/2001]

What equation will find compression ratio regardless of the time it took to compress?

Displaying Large Repetends on Small Calculators [05/31/2002]

How can I find a 16-digit repetend using an 8-digit calculator?

EE Key on a Calculator [10/25/1999]

What does "EE" on the calculator stand for?

Equivalence Relations [08/12/2003]

If I have a function that maps from R to R (where R is the reals) and a set of functions, say O(f), for g where there exist constants c and a in R+ (positive reals), where |g(x)| is less than or equal to c| f(x)| for x greater than a, how would I define a relation, say Q, on the set of functions mapping R to R by putting (g,h) in R iff g-h is in O(f)?

Erlang B [10/22/2002]

I need to know how to calculate the addition of numbers using logarithms: 1 + 2 + 3. There is a step that requires adding numbers that exceed Excel's limits. How can I use logs to add the numbers?

Exact Answers for Square Roots [04/16/2006]

My teacher says that one of the problems with using calculators is that you don't always get exact answers. I don't understand why. Aren't calculators accurate?

Exponents on a Scientific Calculator [08/21/1997]

My problem is that I am not using the EXP key correctly...

Expressing Arccos in Terms of Arctan [02/24/1997]

How do you express Arccos in terms of Arctan?

Fabric Left on a Roll [03/15/2001]

I am going to write a program for my TI-83+ to calculate how many feet of material are left on a roll.

Factorial on TI-83 [09/24/1997]

What is the origin of the TI-83 definition of factorial (in increments of 0.5) and where is it used? What resources would you suggest?

Finding All Combinations of Numbers [07/23/2002]

Programs in C++ and Visual Basic for finding all possible combinations of numbers using a pre-defined set.

Finding an Angle [08/09/2002]

I need to know how to calculate an angle between two points.

Finding Percentages on a Calculator [06/22/2006]

How does the percent key on a calculator work? How do I use it to find a percent of a number?

Finding Pi in C++ [10/10/2001]

I want to write a program in C++ to find the first 100 digits in Pi following the sequence: 4-(4/3)+(4/5)-(4/7)+...

Finding Roots on a Calculator [04/22/2001]

How can I use the equation HPR = (1.667)^(1/5) on a calculator that does not have a fifth root key?

Floating 2 [06/12/2001]

Start with the number 2 on the far left side, then float the number 2 to the far right side; the new number must be three as large as the old number.

Fraction Algorithm [03/19/2002]

I have been having trouble making an application that can convert a finite decimal to a fraction without doing 78349/1000000.

Games for TI Calculators [6/6/1995]

Where can I find programs for a TI-82 calculator?

Generating Permutations With a Computer [06/20/2002]

I want to write a computer program to solve 'Jumble' word puzzles.

Generating Permutations With a Computer [06/20/2002]

I have a friend named REBECCA. How can I generate all the distinguishable permutations of all the letters of her name?

Generating Random Numbers [02/24/2001]

Would you know of any congruential models for the generation of random numbers?

Generating Random Numbers with Specified Probabilities [08/10/2003]

Given an evenly distributed Pseudo Random Number (PRN) generator (with each generated outcome having the same probability), how can I generate outcomes with specified probabilities?

Graphing Peculiarity [07/24/2002]

When I use a calculator to graph one form of an equation it works fine; but when I use a different form, it doesn't work. What's going on?

High School Math Software [7/12/1996]

Where can I get good shareware/freeware programs that deal with high school math topics?

History of Writing Decimals and Number Lines [10/28/1998]

Why, on a number line, are the negative numbers are on the left? When you deal with decimals, why are the whole numbers are on the left?

How a Calculator Determines Values of Trig Functions [03/19/2005]

I'm interested in how my calculator finds the answer of sin(pi/4) or tan(pi/6), for example. Does it use power series?

How a CPU Adds Decimal Numbers [10/22/2000]

How does an 8-bit CPU add up two four-digit decimal numbers, and why does it take four operations to do so?

How Many Triangles? [10/30/2001]

If we join one point on each of the three sides of a triangle to make another triangle, there are three triangles with vertices pointing up. How many triangles will have vertices pointing up if there are n points?

HP-38G Graphic Calculator [08/29/1998]

I'm having trouble graphing on my HP-38G calculator. Can you help?

Implied Multiplication and TI Calculators [05/02/2008]

If I type 36/6(25-11*2) into my TI-85, I get an answer of 2. If I include a multiplication symbol to have 36/6*(25-11*2), I get an answer of 18. I thought that when the 6 is written right up against the parenthesis, the multiplication is implied. Why am I getting two different answers?

Integer Modulus vs. Remainder [03/14/2002]

We were taught by our computer professors that the modulus is the remainder of an integer division, but your discussion leads me to believe this is not quite true.

Interpreting 2^3^2 [04/26/2001]

Why is 2^3^2 interpreted as 2^(3^2) = 512 instead of (2^3)^2 = 64?

Introduction to Fractals [09/02/1998]

Can you give me some basic information on fractals? How would you create one?

Inverse Sine Function on a Calculator [5/14/1996]

Finding Arcsin(y) using a calculator.

Julian to Calendar Date Conversion [02/24/2001]

Can you show me an algorithm to convert Julian date values to calendar date values? For example, Julian date 2451964 = 02/24/2001.

KaleidoTile [11/15/1995]

I would appreciate it if you would tell me a bit about KaleidoTile.

Large Prime Numbers [12/17/1997]

Is there an algorithm to determine whether a very large number is prime?

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