arrow_back Back to Sine, Cosine Rule and Area of a Triangle

Sine, Cosine Rule and Area of a Triangle: Probing Questions

Whether you are looking for a question to stimulate discussion in lesson, or a challenge at the end of a homework, then hopefully you will find these useful.

Contents

Convince Me That... keyboard_arrow_up
Back to Top

I use Convince Me That questions lots in my lessons and homeworks. Providing students with a statement and challenging them to come up with as many different ways of convincing you as possible can lead to some fascinating discussions. The different ways of seeing the same thing can also help improve the depth of students’ understanding. Thanks so much to the Thornleigh Maths Department, in particular Erica Richards, Anton Lewis and Gareth Fairclough for helping me put these together, and we will endeavour to keep adding more!

The cosine rule is related to Pythagoras' Theorem

You know when to use the sine rule or the cosine rule

You can prove the sine rule and the cosine rule

The side opposite the largest angle in a triangle is the longest side of that triangle

You can use the sine and cosine rule on right-angled triangles

VI3 Treatment keyboard_arrow_up
Back to Top

We devised VI3 Treatment as a versatile way of giving students meaningful follow-up work at once we have marked their homework. The idea is that students are challenged to come up with 3 things with certain constraints. These are ideal to use as an extension for students who have got everything correct, and also as further purposeful practise for students who have got a particular question wrong. Use the ideas below and adapt them accordingly, using different numbers where appropriate. Either mark them yourself or better still, get other students to do it. Thanks so much to the Thornleigh Maths Department, in particular Erica Richards, Anton Lewis and Gareth Fairclough for helping me put these together, and we will endeavour to keep adding more! 

Create 3 questions that you need the sine rule (or cosine rule) to answer

Sketch 3 non-right-angled triangles that have an area of 15, marking on the lengths of two size and the size of one angle