Complementary Angle Identities (HSC SSCE Mathematics Advanced): Flashcards

Two angles that sum to $90°$

$\cos \theta$

$\sin \theta$

$\cot \theta$

Cosine

Cofunction identities

$\theta = 90° + 180°n$ (where $n$ is integer)

$\theta = 180°n$ (where $n$ is integer)

$\theta = 180°n$ (where $n$ is integer)

Each function swaps with its cofunction