Trigonometric identities
What Trigonometric identities means in Mathematics A-Level, as defined for AQA, Pearson Edexcel.
Definitions of Trigonometric identities
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Reference: Pearson Edexcel
Known identities used to manipulate expressions, such as sin² θ + cos² θ = 1, tan θ = sin θ / cos θ, and the addition, double angle and harmonic form formulae.
Fundamental identities such as sin²θ + cos²θ ≡ 1, tanθ ≡ sinθ/cosθ, and the addition formulae, used to build logical arguments.
Topics that use Trigonometric identities
- E: Trigonometry (AQA A-Level)
- Trigonometry (Pearson Edexcel A-Level)
Related terms
- Identity
- period
- Periodicity
- principal value
- Radian
- Radian measure
- small-angle approximation
- Algebraic manipulation
Using Trigonometric identities in the exam
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