Absolute Value Functions
The absolute value (ABS) function is the positive value of a number or quantity. Its graph has a very peculiar shape, a V. Since absolute… Read more
Absolute Value Polynomials
What would you guess the absolute value of a polynomial function would look like? Try some here. I think you will be very surprised. Can… Read more
CO2 Growth
Spreadsheets offer us a nearly unlimited ability to develop and learn from case studies using real world data. We will focus mainly on climate change… Read more
Composition of Functions
One of the most powerful aspects of the mathematics of functions is our ability to treat them as abstract quantities (essentially numbers) and then combine… Read more
Exploring Triangles
Create, manipulate, and explore triangles in this live interactive spreadsheet. On the surface, a triangle is being drawn on a graph, but the real magic… Read more
Exponential Functions
What if you created a function where the exponent is a variable? As you might expect, this would be called an exponential function. When you… Read more
Hindu Algebra Problem
This problem is typical of the earliest algebra problems that likely came out of India. It is interesting historically, and it is the kind of… Read more
Interest
Which form of interest, simple or compound, is the fairest? If you were buying a house or a car which would you rather have, which… Read more
Inverse of a Function
Spreadsheets make it very easy to switch axes and add graphs. They enable students to play with what may have been difficult and abstract concepts… Read more
Inverse of Linear Functions
What does a linear function look like when we interchange the inputs and outputs, that is make the x-axis the y-axis and vice versa. Read more
Inverse Variation
The variables in most of the functions we are used to working with vary directly, as one goes up the other goes up. What do… Read more
Linear Functions
Linear functions are the most important family of functions. They pervade our everyday lives and our work. Their graph is a line, and their general… Read more
Lissajous Figures
We often see Lissajous figures in old sci-fi movies because they are so cool. As you play with them I think you will find them… Read more
Magic Number (Infinite Series)
What if you made a series of unit fractions with the odd numbers as their denominator, added the first two together, subtracted the next one,… Read more
Moore’s Law
It was one of the most amazing visions of the future ever made. In 1965 Gordon Moore, one of the founders of Intel, proposed a… Read more
Motion Problems
George is in New York and Martha is in Washington. They leave at the same time and follow the same road to meet each other… Read more
Normal Distribution
Most museums with math exhibits have a Pascal’s triangle made up of pegs with balls falling down between them and bouncing off of them. One… Read more
Parametric Equations
Parametric equations are powerful tools to model projectile motions and to graph things that are not functions like circle or ellipses. The x and y… Read more
Parentheses and Pi
Parentheses are very important in spreadsheets because like all programming, spreadsheet formulas have to be very specific. A big formula, especially one like Viete’s approximation… Read more
Pascal’s Triangle
Another famous pattern, Pascal’s triangle, is easy to construct and explore on spreadsheets. Create a formula for any cell that adds the two cells in… Read more
Polynomial Functions
Polynomial functions are not limited to the highest term and while that term is most important in determining the shape of its graph, additional terms… Read more
Power Functions
Adding an exponent, sometimes referred to as a ‘power’, to the input variable of a linear function that passes through the origin creates a power… Read more
Projectile Motion
Let’s do a little target practice with this spreadsheet projectile simulator, which will map out the flight path of an arrow shooting toward a target. Read more
Quadratic Functions
What does each of the coefficients do? How does it change the graph of the parabola. What does a do, what does c do and… Read more
Rate of Growth
We look at world population over the past 60+ years and ask whether the earth’s population is growing faster or slower today. Is it out… Read more
Rule of 72
The rule of 72 is an old banker’s rule of thumb to find out how long it will take to double your money at different… Read more
Sine Function
Spreadsheets are not limited to algebraic functions, they can also display trigonometric functions. We are modeling the sine function, but you can try any of… Read more
Solar System
When I was young I loved to play with planetary data, to explore their patterns, to learn more about astronomy, and to deal with large… Read more
Solving Equations
Typical algebra courses start with equations and solving equations and then move to graphing and functions. We start with functions and use them to solve… Read more
Solving Equations Digitally
This Lab introduces a method for solving or estimating the solution to an equation digitally that can be applied to many types of equations. This… Read more
Syracuse Problem
I built a Lab for you to play with the Syracuse Problem and to learn to use spreadsheets to play with like problems in fun… Read more
Systems of Equations
Solving systems of equations sometimes called simultaneous equations with graphs is simply a matter of finding out where they intersect. One of the most valuable… Read more
The Chessboard
We take that great old problem of the inventor of chess and the ruler of India and use it to see how powers of 2… Read more
Triangular Numbers
1, 3, 6, 10… are called the triangular numbers because they can be stacked up to form a triangle. They are very interesting numbers, and… Read more
What is x?
What is “x”? Or how do we represent variables and functions on spreadsheets? Read more