The Interactive Sin/Cos Diagram
The following interactive diagram shows the relationship between sin(θ) and cos(θ), each angle gives us a different triangle, and each triangle has a corresponding square. Listed below are some of the most interesting angles:
a) 63.434948822922010648427806279547... (sqrt5 triangle)
b) 53.130102354155978703144387440907... (543 triangle)
These angles are also quite interesting: 36, 45, 54, 72.