In triangle ABCABCABC, side AB AB\,AB has length 5 cm, side BC BC\,BC has length 9 cm and side AC AC\,AC has length 7 cm.
Find the cosine of angle ACBACBACB, giving your answer as a fraction in its simplest form.
Find the exact area of the triangle.
18 exam-style questions on Edexcel AS Level Maths Trigonometric Ratios, covering 9.1 The Cosine Rule, 9.2 The Sine Rule, 9.3 Areas of Triangles, 9.4 Solving Triangle Problems, 9.5 Graphs of Sine, Cosine and Tangent, and 9.6 Transforming Trigonometric Graphs. Each one has a worked solution and a mark scheme showing where the marks go.