Using the sine and cosine rules
I can use the formula for the cosine rule and the sine rule.
Using the sine and cosine rules
I can use the formula for the cosine rule and the sine rule.
These resources will be removed by end of Summer Term 2025.
Lesson details
Key learning points
- The cosine rule is useful when you know three sides and an angle are involved
- The sine rule is useful when you know two pairs of sides and angles are involved
Keywords
Sine rule - The sine rule is a formula used for calculating either an unknown side length or the size of an unknown angle.
Cosine rule - The cosine rule is a formula used for calculating either an unknown side length or the size of an unknown angle.
Common misconception
Pupils may be uncertain over how to start a problem.
Encourage pupils to draw a diagram if one is not provided and then to annotate the diagram with any given information as a first step. If a diagram is given then pupils should annotate that.
To help you plan your year 11 maths lesson on: Using the sine and cosine rules, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 11 maths lesson on: Using the sine and cosine rules, download all teaching resources for free and adapt to suit your pupils' needs.
The starter quiz will activate and check your pupils' prior knowledge, with versions available both with and without answers in PDF format.
We use learning cycles to break down learning into key concepts or ideas linked to the learning outcome. Each learning cycle features explanations with checks for understanding and practice tasks with feedback. All of this is found in our slide decks, ready for you to download and edit. The practice tasks are also available as printable worksheets and some lessons have additional materials with extra material you might need for teaching the lesson.
The assessment exit quiz will test your pupils' understanding of the key learning points.
Our video is a tool for planning, showing how other teachers might teach the lesson, offering helpful tips, modelled explanations and inspiration for your own delivery in the classroom. Plus, you can set it as homework or revision for pupils and keep their learning on track by sharing an online pupil version of this lesson.
Explore more key stage 4 maths lessons from the Non right-angled trigonometry unit, dive into the full secondary maths curriculum, or learn more about lesson planning.
Licence
Starter quiz
6 Questions
Exit quiz
6 Questions
4 cm -
$$a=3$$ cm , $$b = $$? cm and $$c=5$$ cm
13 cm -
$$a=5$$ cm , $$b = 12$$ cm and $$c=$$? cm
7 cm -
$$a=$$? cm , $$b = 24$$ cm and $$c=25$$ cm
15 cm -
$$a=8$$ cm , $$b = $$? cm and $$c=17$$ cm
60 cm -
$$a=11$$ cm , $$b = $$ ? cm and $$c=61$$ cm

