union
What union means in Mathematics A-Level, as defined for AQA, Pearson Edexcel, WJEC.
Definitions of union
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Reference: WJEC
The symbol ∪ expresses disjoint solution regions as a set, connecting intervals that cannot be satisfied simultaneously by any real number.
Combining sets, meaning 'or', used to join separate solution intervals and to represent the probability of event A or event B occurring.
The connective "or" is required for disjoint inequality solution regions, correctly represented using the union symbol.
Combining two inequalities joined by 'or' means taking the union, written with ∪, and the addition law uses P(A ∪ B).
The event A or B or both, denoted A ∪ B.
Topics that use union
- M: Probability (AQA A-Level)
- OT1: Mathematical argument, language and proof (AQA A-Level)
- Overarching theme 1: Mathematical argument, language and proof (Pearson Edexcel A-Level)
- Algebra and Functions (AS Unit 1: Pure Mathematics A) (WJEC A-Level)
- Overarching themes - Mathematical argument, language and proof (WJEC A-Level)
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