Michelle Du Toit begins this inivesigation by using Mathomat shape 33, the trapezium, to draw parallel sides. She the encloses the trapezium in a triangle.
Print out the two pages of activity sheets of this investigation. Then follow the steps that Michelle uses to illustrate circle theorems one and two using accurate construction work with Mathomat.
These theorems are proved in this investigation using the equilateral triangle and two of the rhombuses in Mathomat.
Circle theorem 1 can be stated as, "The line drawn from the centre of a circle perpendicular to the chord, bisects the chord. We prove this theorem by drawing with Mathomat - this involves using the square, shape 25, to halve the the equilateral triangle, shape 5.
Circle theorem 2 can be stated as, "The perpendicular bisector of chord passes through the centre of the circle". We use Mathomat to prove this theorem by drawing a square, shape 25, within a circle.
The circle is a very common object in our world, one that is not made up of straight lines. Think of many watch faces, dinner plates and car wheels. It is important to be able to measure and transform circular objects in the same way that we work with straight sided objects. In design and engineering circle theorems can be used to calculate missing angles without the use of a protractor. Some people argue that circle theorems are an important introduction to rigorous mathematical proof. Many people also regard circle theorems as reprsenting the beauty of mathematics.
Get a glimpse of the tremendous potential for using Mathomat as an aid to teaching mathematics.
Using a series of Mathomat products and templates, learn maths and geometry with Pr. Chris Tisdell.
Purchase official Mathomat templates, booklets and teaching resources for your child or classroom.
Read through some interesting studies and research that make use of Mathomat templates.
