The Shoemaker's Knife

Topic:Area

The area enclosed by the semi-circles centred O, X and Y and on the same diameter is called the Shoemaker's Knife. The radii of the two smaller semi-circles are variable. This is illustrated in the diagram below.

New Resources

Rotating Plane Figures to Form Solids
Squaring a Rectangle (PST Version)
Conditional Probability in Two-Way Tables
Angle Addition Postulate (V2) - Integer Solutions
Isosceles Right Triangle

Discover Resources

Constructing an Equilateral Triangle
Wave Superposition
Face Creation Through Reflection- Jennifer Lopez period 6
รูปคลี่พีระมิด
Kite (Scaffolded Discovery)

Discover Topics

Translation
Circle
Integers
Continuity
Arithmetic Mean