Trigonometry

Sine, cosine and tangent for any angle: solving triangles, sketching graphs, proving identities and solving equations. This is DfE content area E (Trigonometry). In Year 1 all angles are in degrees — radians arrive in Year 2.

• An Overview — the big idea, the language, the core techniques and the common mistakes

The content statements

• Sine and Cosine Rules — the sine rule and the ambiguous case, the cosine rule, area = ½ab sin C and bearings
• Trigonometric Graphs — sin, cos and tan for any angle, symmetry, periodicity, exact values and transformations
• Trigonometric Identities — tan θ ≡ sin θ / cos θ, sin²θ + cos²θ ≡ 1 and proving identities
• Trigonometric Equations — solving in a given interval, quadratics in sin or cos, and equations such as sin(nθ + α) = k

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Each page has step-by-step notes, several worked examples, a quick-reference grid and ten practice questions with fully worked solutions.