Trigonometric Identities

Even-Odd Identities

sin (-u)= -sin u

sec (-u)= sec u

csu (-u)= -csc u

tan (-u)= tan u

cos (-u)= cos u

cot (-u)= cot u

Recipricoal Identities

Sin u= 1/csc u

csc u= 1/sin u

Cos u=1/sec u

sec u= 1/cos u

Tan u=1/cot u

cot u=1/tan u

Quotient Identities

tan u= sin u/cos u

cot u= cos u/sin u