When should you use the sine rule and when should you use the cosine rule?

The sine rule can be used when we either know:a) the length of two sides A and B and an angle that is not the corner where A and B meetb) two angles and the length of one side
The cosine rule can be used when we know:a) all three side lengths orb) when we have the length of sides A and B and the angle of the corner where A and B meet

JB
Answered by Joseph B. Maths tutor

3289 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

What is Pythagoras's theorem?


Steve wants to put a hedge along one side of his garden. He needs to buy 27 plants for the hedge. Each plant costs £5.54 Steve has £150 to spend on plants for the hedge. Does Steve have enough money to buy all the plants he needs?


Solve the simultaneous equations: 3x + y = -9, x^2 + 2x - 3 = y


Expand and simplify 3(m + 4) – 2(4m + 1)


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning