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


Special angles



General angles


α = basic/associated acute/reference angle


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

cos (-θ°) = cosθ°
sin (-θ°) = - sinθ°
tan (-θ°) = - tanθ°

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 : secθ° = 1/cosθ°, cos θ° 0
cosecant : cosecθ° = 1/sinθ°, sin θ° 0
cotangent : cotθ° = 1/tanθ°, tan θ° 0


sin²θ° + cos²θ° = 1
sec²θ° = 1 + tan²θ°
cosec²θ° = 1 + cot²θ°


Addition & Subtraction Formulae
sin (θ ± α) = sin θcosα ± cosθsinα
cos (θ ± α) = cosθcosα sinαsinθ


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


a cosθ° ± b sinθ°
a cosθ° ± b sinθ° = R cos (θ α)°
a sinθ° ± b cosθ° = R cos (θ ± α)°



Amaths3
Amaths4
Amaths5
Amaths1

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