Posted by
**rick** on
.

The Pythagorean Theorem gives the relationship between the sides of a right triangle. The following identities show the relationships between the trigonometric functions of a particular angle.

sin2 θ + cos2 θ = 1

tan2 θ + 1 = sec2 θ

1 + cot2 θ = csc2 θ

Why then are these referred to as the Pythagorean Identities?