✸ Trigonometric ratios of angles ✸ Graphs of sinθ, cosθ and tanθ ✸ Trigonometric ratios of 30º, 45º and 60º ✸ Secant, cosecant and cotangent ✸ Trigonometric equations ✸ Pythagoras theorem ✸ Compound angle formula ✸ Double angle formula ✸ The t–formula ✸ The form acosθ + bsinθ ✸ The factor formulae ✸ The sine and cosine rule ✸ The area of a triangle