Pythagoras’ Theorem and Trigonometry

Where sine, cosine and tangent stop being ratios in a triangle and become functions in their own right. All angles in this qualification are measured in degrees.

• An Overview — the big idea, the language, the key formulae and which rule to use

The specification statements

• PT1 · Ratios of Any Angle — the unit circle, CAST, exact values, and the three graphs
• PT2 · The Sine and Cosine Rules — non-right-angled triangles, including the ambiguous case
• PT3–PT4 · Trigonometric Identities — tan ≡ sin ÷ cos, and sin² + cos² ≡ 1
• PT5 · Trigonometric Equations — finding every solution in a given interval
• PT6 · 2-D and 3-D Problems — cuboids, pyramids, and the angle of greatest slope

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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.