principal value
What principal value means in Mathematics A-Level, as defined for AQA, OCR, Pearson Edexcel, WJEC.
Definitions of principal value
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Reference: WJEC
A value α = arcsin(k), arccos(k), or arctan(k) calculated before secondary solutions in the base cycle are determined using symmetry.
The unique solution to an inverse trigonometric function that lies within a restricted range (e.g., -π/2 ≤ arcsin(x) ≤ π/2). Your calculator provides this value.
The unique solution to an inverse trigonometric function within a restricted range (e.g., -π/2 ≤ arcsin(x) ≤ π/2).
The single value returned by an inverse trigonometric function within its defined restricted range.
The unique angle selected by an inverse trigonometric function from its specified principal range.
Topics that use principal value
- E: Trigonometry (AQA A-Level)
- Trigonometry (OCR A-Level)
- Trigonometry (Pearson Edexcel A-Level)
- Trigonometry (AS Unit 1: Pure Mathematics A) (WJEC A-Level)
Related terms
Using principal value in the exam
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