# C2 Core Maths - Chapter 2 Notes

Chapter 2 - The sine and cosine rules

- Created by: Megan Wilkinson
- Created on: 19-05-12 10:45

First 176 words of the document:

AS Core Maths 2 Revision

Core 2 Chapter 2

The sine and cosine rule

Key points to remember

The sine rule is:

(a ÷ sinA) = (b ÷ sinB) = (c ÷ sinC) OR...

(sinA ÷ a) = (sinB ÷ B) = (sinC ÷ c)

N.B These should all be written as fractions, not as division

sums

Then most likely solved making one equal to the other.

You can use the sine rule to find an unknown side in a triangle

if

you know two angles and the length of one of their opposite

sides.

You can use the sine rule to find and unknown angle in

a triangle

given that you know the lengths of two sides and one of their

opposite angles.

if the angle you are finding is opposite the larger of the two

sides, then there are two possible values for the angle, unless

it

is a right angle.

The cosine rule is:

a2 = b2 + c2 - 2bccos A

## Comments

No comments have yet been made