Identities
Subject:
Trigonometry [1]
Pythagorean Identities
sin2 θ + cos2 θ = 1
tan2 θ + 1 = sec2 θ
cot2 θ + 1 = csc2 θ
Odd/Even Identities
sin (–x) = –sin x
cos (–x) = cos x
tan (–x) = –tan x
csc (–x) = –csc x
sec (–x) = sec x
cot (–x) = –cot x