This method for finding the centre, and by extension the equation, of a circle given three non-colinear points, brings the ancient textbook master Euclid onto Descartes’ coordinate plane and right into the 21 century classroom.

# Tag: as core mathematics

Geometric Progressions, essential for Core AS mathematicians, appear in Victorian textbook, Synopsis of Elementary Results. In the case where the sum to infinity exists, there is a nice proof by similar triangles.