Graphs of Sine and Cosine 1.2 An applet illustrating how the graphs of sine and cosine are related to the unit circle ... of the Tangent to a Parabola 2.1 An applet illustrating how the tangent to a ...

Descartes’ theorem, a cornerstone of geometry, defines the relationship between four mutually tangent circles. But for centuries, generalizing the equation to more than four circles had eluded ...

A tangent is a straight line which touches the circle at a point but does not cut through the circle. There are two theorems involving tangents. The angle between a tangent and a radius is 90°..