- You can subtract as well as add fractions.
- You can divide the number line into equal parts and choose the … Continue Reading ››

# Tag Archives: Web Sketchpad

# Adding Fractions on a Number Line

# A Plethora of Hyperbola Constructions

# Constructing the Pi-Petal Rose

# Tweaking the Expanding Circle Construction

# The Expanding Circle Construction

# The Varied Paths to Constructing a Rhombus

In how many different ways can you build a rhombus that stays a rhombus when its vertices are dragged? This assignment, a mainstay of Sketchpad workshops, invariably leads to great discussions because there are a multitude of ways to construct a rhombus, with each method highlighting different mathematical properties of the quadrilateral.

# A Trio of Parabola Constructions

In my prior blog posts, I've presented methods for constructing ellipses using Web Sketchpad and paper folding. The other conic sections are feeling a bit left out, so let's explore some techniques for constructing parabolas.

All three Web Sketchpad models below (and here) are based on the distance definition of a parabola: The set … Continue Reading ››

# An Interactive Approach to Finding nth Roots

When students find the nth roots of a complex number, they use de Moivre's Theorem and a fair bit of calculation and trigonometry. In this blog post, I'm going to approach the topic from a more visual perspective and make use of the following geometric way to think about complex number multiplication: To multiply two complex … Continue Reading ››

# Beam of Light

This month's post is based on a problem that appears in Martin Gardner's *Sixth Book of Mathematical Diversions from Scientific American*. Below (and here) is a Web Sketchpad model of an orderly forest. There is a tree at every point whose *x*- and *y*-coordinates are both integers. These are the green points. … Continue Reading ››