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High School Archive

Browse High School Calculators and Computers
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Binary Conversion [01/07/1998]

In an adult computer course we are supposed convert binary numbers to real numbers and binary to hexadecimal.

Decimal To Fraction Conversion [06/25/1998]

I am trying to find a method (one that can be programmed on a PC) to convert the decimal part of a real number to a fraction represented by integers for the numerator and denominator.

Dividing by Zero on a Calculator or Computer [2/12/1996]

Whenever I try to divide a number by 0, I get an error on both my computer and calculator. Please explain to me why this can't be done.

Year 2000 (Y2K) Problem [07/26/1998]

Can you explain the Year 2000 problem in layman's terms? Why is it so hard to fix?

2D Graphing Software: Maple [7/15/1996]

Could you recommend any PC software that could help me study hyperbolas and other curves?

3-D Points to a 2-D computer screen [07/25/1997]

I am trying to write a 3-D graphics engine that takes 8 points with their own (X,Y,Z) coordinates to plot a CUBE in 3-D space...

Algorithm for Finding Pi, in C [02/14/1998]

I would like to know how to implement various algorithms for finding pi in the C language.

Algorithm for Simple Fractional Exponents [03/14/2002]

How can I explain to my program how to resolve simple fractional exponents using only addition, subtraction, multiplication, division, square, and square root?

Analog-to-Digital Conversion [02/07/2001]

How do I do an analog-to-digital conversion of text and strings, or of tactile senses?

Arbitrary-Precision Arithmetic [08/08/2003]

How could I use QBasic V4.5's math to compute numbers that are greater than 10^15 in the quickest way, and yet display every single digit in the product?

Arccos Algorithms and Computer Calculators [03/21/1998]

I need an algorithm to find the arccos of a value.

Arc Midpoint [07/17/2001]

I'm trying to figure out the midpoint of an arc where I know the start and end points of the arc and the radius only.

ASCII or EBCDIC? [05/11/2002]

Given a bit sequence like 01000001, how can I tell if it's ASCII or EBCDIC?

Binary Division and Negative Binary Numbers [02/24/2002]

Suppose you enter 11111000 into a binary calculator. How would it know whether that is to be 248 or -8? How does the computer begin the division process? What does it do when it cannot right shift the bits?

Binary Search Trees [02/06/2003]

Which of the following sequences represent(s) an order of insertion that will result in a binary search tree where each node in the tree has the same number of nodes in its left and right subtrees?...

Binary Subtraction [07/04/2003]

I need help understanding the rules of subtracting binary numbers when the subtrahend is larger then the minuend.

Bits, Bytes [04/28/2003]

A Web page of 10 megabytes is being retrieved from a Web server. What is the time to transfer the page over a modem operating at 28.8kbps?

Boolean Numbers [04/01/2003]

Our C Programming course said a Boolean number was a number that was either true or false. I'm not sure what a true or false number is.

C++ Abundant Number Program [01/26/2001]

Is there a computer science C++ formula that allows the user to find whether a number is abundant, deficient, or perfect?

Calculate the Derivative for Sqrt(x^5) [03/09/2003]

Why does the calculator fail when I calculate the derivative for sqrt(x^5)?

Calculating Sine Without Using the Sine Key or a Table [01/02/2004]

I'm curious what the arithmetic is behind the trig functions. For example, to evaluate sin(48), what math process could I use if I didn't have a calculator?

Calculator Addition [6/30/1996]

How does a calculator add?

Calculator for Algebra I and Physical Science [8/11/1995]

My son is taking Algebra I and a first course in physical science this semester. Do you have a recommendation for a calculator?

Calculators and Irrational Numbers [05/02/2001]

When I square the square root of 11 on any calculator, I get the answer 11 (exactly). That seems to indicate that the square root of 11 is a rational number, but it's not. Can you explain this?

Calculators and Trig Functions [12/03/1996]

How do calculators solve trigonometric functions? Is there any way to determine the y value on a graph of the arc subtended by the angle theta?

Calculators - CORDIC Method [05/16/1999]

How can a computer or calculator calculate square roots, cube roots, Xth root, x^y, logarithm, sine, cosine, ...?

Chaos Theory and Computers [2/4/1996]

I have happened upon an equation which can create a fractal that demonstrates chaos theory graphically. Since the computer cannot learn, and chaos theory is based on a lack of pattern, how is the computer able to compute this?

Check Digits in Payroll or Stock Numbers [11/16/1996]

What is the set of calculations required to get a unique check digit?

Combining Multiple Signals in Data Transmission [02/18/2001]

How can a cable carry so much information? How can data carriers compress multiple signals and then pull them apart again?

Combining Numbers Reversibly [06/04/2003]

I have been trying to find a way of getting two different numbers, combining them through a formula that will give a final number. From that new number it should be possible to get the two numbers back.

Compute 16-bit One's Complement Sum [03/20/2002]

In my TCP/IP book it says, "to compute the IP checksum for outgoing datagram, the value of checksum field is set to zero, then the 16-bit one's complement sum of the header is calculated (i.e. the entire header is considered a sequence of 16-bit words)" - but I do not know how to compute the one's complement sum.

Computers and Calculators in Math Today [12/6/1995]

For a term paper on math, I need to know how computers and calculators play a big part in math today.

Computers and Trigonometric Functions [02/11/1997]

How do computers and calculators calculate values for sine, cosine, and tangent?

Computers: Defining Logical Operations [05/21/1998]

Can you tell me the meaning of the following logical operations: AND, OR, XOR, NAND, NOR, NOT?

Converting a Decimal Hour [11/22/2001]

How do I convert 1.7 hours into hours, min, sec? Is there a standard formula I can use? I would like to put this into an Excel spreadsheet.

Converting Bits to Megabytes [02/12/2001]

The human brain will store 100 trillion bits in its lifetime. How many million megabytes can your brain store?

Converting HH:MM to Minutes in Excel [06/25/2003]

Is there an easy method (i.e. any formula or a macro) for converting Hours:Minutes (HH:MM) to Minutes in Excel?

C++ Program to Convert Decimal to Binary [10/26/1999]

Can you show me a C++ routine that converts decimal numbers to binary?

Cyclic Redundancy Check [06/26/2002]

I understand how cyclic redundancy checks work, but I fail to see how appending zeros to the message string (before the division) provides an advantage.

Data Compression [08/10/2003]

Is there an algorithm that can reduce any binary number to a much smaller binary number, then later be reversed to regain the original number? It has to work for any binary number.

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