I. Relations de base

cos² + sin² = 1

cos (-) = cos cos ( - ) = - cos cos ( + ) = - cos cos ( - ) = sin cos ( + ) = - sin

sin (-) = - sin sin ( - ) = sin sin ( + ) = - sin sin ( - ) = cos sin ( + ) = cos

tan (-) = - tan cotan (-) = - cotan

II. Formules en t

t = tan
1 + t² =

cos =
sin =
tan =

III. Formules d'addition

cos (a - b) = cos a cos b + sin a sin b sin (a - b) = sin a cos b - cos a sin b cos (a + b) = cos a cos b - sin a sin b sin (a + b) = sin a cos b + cos a sin b tan (a + b) = tan (a - b) = cos 2a = cos²a - sin²a          = 2 cos²a - 1          = 1 - 2 sin²a

cos² a = sin² a = sin 2a = 2 sin a cos a tan 2a =

IV. Arcs remarquables

(°)	0	30	45	60	90
(rad)	0
sin	0				1
cos	1				0
tan	0		1

V. Formules de transformation de produit en somme

cos a cos b = (cos(a - b) + cos(a + b))
sin a sin b = (cos(a - b) - cos (a + b))
sin a cos b = (sin(a + b) + sin (a - b))
cos a sin b = (sin(a + b) - sin (a - b))