1. Sine and Cosine Rule- Which One to Use?

2. Two Sides and Included Angle To find side x, use the …. cosine rule To find angle Y, use the … sine rule 7cm 10cm 75 o x Y Z To find angle Z, use …. angle sum of triangle

3. Two Angles and a Side To find angle A… use angle sum of triangle To find side b…. use sine rule To find side c…. use sine rule

4. Three Sides 8cm 12cm 15cm To find angle P…. P use the cosine rule To find angle Q…. Q use the sine rule R To find angle R… use angle sum of triangle

5. Top Trigonometric Tip…. Always use the sine rule where possible, it is easier to use a 2 = b 2 + c 2 – 2bcCosA Remember:- sine rule cosine rule