Mathematics A-Level
addition and subtraction identities
What addition and subtraction identities means in Mathematics A-Level, as defined for WJEC.
Definition of addition and subtraction identities
Check what you remember
Read the wording for your board, then hide it and explain addition and subtraction identities in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: WJEC
Formulas where cos has minus for addition and plus for subtraction, and tan has (tan A ± tan B) / (1 ∓ tan A tan B).
Topics that use addition and subtraction identities
- Trigonometry (A2 Unit 3: Pure Mathematics B) (WJEC A-Level)
Related terms
- composite trigonometric arguments
- domain and range
- double angle formulas
- exact trigonometric values
- harmonic form
- inverse trigonometric functions
- mixed angle equations
- power reduction identities
Using addition and subtraction identities in the exam
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