TRIGONOMETRIC FUNCTIONS
sin °= cos (90 - )°
cos =sin (90 - )°


Special angles



General angles


= basic/associated acute/reference angle


For any ° with basic
sin ° = sin [1st + 2nd]
sin ° = -sin [3rd + 4th]
cos ° = cos [1st + 4th]
cos ° = -cos [2nd + 3rd]
tan ° = tan [1st + 3rd]
tan ° = -tan [2nd + 4th]

cos (-°) = cos°
sin (-°) = - sin°
tan (-°) = - tan°

Sine, Cosine, Tangent Graphs
sin 0° = 0
sin 30° = 0.5
sin 90° = 1
sin 150° = 0.5
sin 180° = 0
sin 210° = -0.5
sin 270° = -1
sin 330° = -0.5
sin 360° = 0


cos 0° = 1
cos 60° = 0.5
cos 90° = 0
cos 120° = -0.5
cos 180° = -1
cos 240° = -0.5
cos 270° = 0
cos 300° = 0.5
cos 360° = 1


tan 0° = 0
tan 45° = 1
tan 90° = undefined
tan 135° = -1
tan 180° = 0
tan 225° = 1
tan 270° = undefined
tan 315° = -1
tan 360° = 0


secant : sec° = 1/cos°, cos ° 0
cosecant : cosec° = 1/sin°, sin ° 0
cotangent : cot° = 1/tan°, tan ° 0


sin²° + cos²° = 1
sec²° = 1 + tan²°
cosec²° = 1 + cot²°


Addition & Subtraction Formulae
sin ( ± ) = sin cos ± cossin
cos ( ± ) = coscos sinsin


Double Angle Formula
cos2A = cos²A - sin²A = 2cos²A - 1 = 1- 2sin²A
sin2A = 2sinAcosA


a cos° ± b sin°
a cos° ± b sin° = R cos ( )°
a sin° ± b cos° = R cos ( ± )°



Amaths3
Amaths4
Amaths5
Amaths1

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