Go to content
IMPORTANT: The multiple MathsNet domain names will soon be rationalised to just the single domain name of www.mathsnet.com. You are currently using mathnetap.com which will become unavailable soon. Please update your favourites/bookmarks to www.mathsnet.com as soon as possible. mathnetap
These formulae are often refered to as the addition formulae:
\sin(A \pm B) = \sin A \cos B \pm \cos A \sin B
\cos(A \pm B) = \cos A \cos B \mp \sin A \sin B
\tan(A \pm B) = \displaystyle \frac{\tan A \pm \tan B}{1 \mp \tan A \tan B}
Change
 Steps  
All
Change
 Steps  
All
O
O
O
O
    
+
r
-
    

Software/Applets used on this page

jsMath
This page uses jsMath
You can get a better display of the maths by downloading special TeX fonts from jsMath. In the meantime, we will do the best we can with the fonts you have, but it may not be pretty and some equations may not be rendered correctly.

Glossary

addition formulae

the trigonometrical formulae:
sin(A+B)=sinAcosB+cosAsinB
sin(A-B)=sinAcosB-cosAsinB
cos(A+B)=cosAcosB-sinAsinB
cos(A-B)=cosAcosB+sinAsinB

union

The union of two sets A and B is the set containing all the elements of A and B.

Full Glossary List

This question appears in the following syllabi:

SyllabusModuleSectionTopicExam Year
AP Calculus AB (USA)1TrigonometryAddition formulae-
AP Calculus BC (USA)1TrigonometryAddition formulae-
AQA A-Level (UK - Pre-2017)C4TrigonometryAddition formulae-
AQA A2 Maths 2017Pure MathsFurther TrigonometryAddition Formulae-
AQA AS/A2 Maths 2017Pure MathsFurther TrigonometryAddition Formulae-
CBSE XI (India)Sets and FunctionsTrigonometric FunctionsAddition identities e.g. sinx +siny sin(x+y) etc.-
CCEA A-Level (NI)C4TrigonometryAddition formulae-
CIE A-Level (UK)P2TrigonometryAddition formulae-
Edexcel A-Level (UK - Pre-2017)C3TrigonometryAddition formulae-
Edexcel A2 Maths 2017Pure MathsTrigonometric Problem SolvingAddition Formulae-
Edexcel AS/A2 Maths 2017Pure MathsTrigonometric Problem SolvingAddition Formulae-
I.B. Higher Level3TrigonometryAddition formulae-
Methods (UK)M2TrigonometryAddition formulae-
OCR A-Level (UK - Pre-2017)C3TrigonometryAddition formulae-
OCR A2 Maths 2017Pure MathsFurther Trig Identities and EquationsAddition Formulae-
OCR MEI A2 Maths 2017Pure MathsFurther Trig Identities and EquationsAddition Formulae-
OCR-MEI A-Level (UK - Pre-2017)C4TrigonometryAddition formulae-
Pre-Calculus (US)C4TrigonometryAddition formulae-
Pre-U A-Level (UK)2TrigonometryAddition formulae-
Scottish (Highers + Advanced)HM2TrigonometryAddition formulae-
Scottish HighersM2TrigonometryAddition formulae-
Universal (all site questions)TTrigonometryAddition formulae-
WJEC A-Level (Wales)C4TrigonometryAddition formulae-