There are three main trigonometric functions - Sine θ (sin θ), Cosine θ (cos θ) and Tangent θ (tan θ). ... 45°, 60°, and 90°. But it is difficult to memorise the values.

Learn and revise trigonometric ratios of sine, cosine and tangent and calculate angles and lengths in right-angled triangles with GCSE Bitesize AQA Maths.