Help your students prepare for their Maths GCSE with this free cosine rule worksheet of 39 questions and answers
The cosine rule is the relationship between one angle within a triangle and its three sides. The cosine rule states that a²=b²+c²-2bc cos(A) where a, b and c are the lengths of the sides of the triangle and A is the angle opposite side a.
The cosine rule can be used to work out missing side lengths and missing angles in non right-angled triangles.
To find the missing information, we put the values we know into the cosine rule and then solve the equation to find the missing length. When working out a missing angle we will need to use the inverse trigonometric function cos-1.
Be sure not to round your answers too early in your calculation when using the cosine rule. Also pay close attention to the specified number of decimal places or significant figures in your answer.
There will be students in your class who require individual attention to help them succeed in their maths GCSEs. In a class of 30, it’s not always easy to provide.
Help your students feel confident with exam-style questions and the strategies they’ll need to answer them correctly with our dedicated GCSE maths revision programme.
Lessons are selected to provide support where each student needs it most, and specially-trained GCSE maths tutors adapt the pitch and pace of each lesson. This ensures a personalised revision programme that raises grades and boosts confidence.