Mathematics A-Level
Small-angle approximations
What Small-angle approximations means in Mathematics A-Level, as defined for Pearson Edexcel.
Definition of Small-angle approximations
Check what you remember
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Reference: Pearson Edexcel
For small angles measured in radians, sine and tangent can be replaced by θ, and cosine by 1 − θ²/2.
Topics that use Small-angle approximations
- Trigonometry (Pearson Edexcel A-Level)
Related terms
- Arcsin, arccos and arctan
- area of a triangle
- Asymptotes
- Domain
- Domains of reciprocal functions
- Equations involving multiples of the unknown angle
- Exact values
- Fundamental trigonometric identities
Using Small-angle approximations in the exam
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