rationalising denominators
What rationalising denominators means in Mathematics GCSE, as defined for AQA, Pearson Edexcel.
Definitions of rationalising denominators
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Reference: Pearson Edexcel
Multiplying numerator and denominator by the same root, or by the conjugate of a two-term denominator, so no root is left in the denominator.
Removing the surd from the bottom by multiplying numerator and denominator by that surd, or by the conjugate for a binomial denominator.
Topics that use rationalising denominators
- Structure and calculation (AQA GCSE)
- Number - Structure and calculation (Pearson Edexcel GCSE)
Related terms
- denominator
- equivalent fractions
- Exact value
- Formal written methods
- fraction
- improper fraction
- Integer
- inverse operations
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