y^2 + x^2 = 1

This entry is based on the prologue for the book Elliptic Tales: Curves, Counting, and Number Theory (challenging but quite fun reading on the morning Tube commute!): is the familiar equation for the unit circle and in the prologue the authors show how a straight line with a rational slope intersects a circle at two… Read More y^2 + x^2 = 1