Mathematics A-Level
Rationalising denominators
What Rationalising denominators means in Mathematics A-Level, as defined for Pearson Edexcel.
Definition of Rationalising denominators
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Reference: Pearson Edexcel
Multiplying numerator and denominator by a suitable surd or conjugate so the denominator no longer contains a surd.
Topics that use Rationalising denominators
- Algebra and functions (Pearson Edexcel A-Level)
Related terms
- Algebraic division by linear expressions
- Amplitude
- Asymptote
- Comparing coefficients
- Completing the square
- Composite function
- Conjugate
- Discriminant
Using Rationalising denominators in the exam
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