Stage: 4 and 5 Challenge Level: 
Multiply the numerator and denominator of each term by a convenient expression to rationalise the denominator.
Powers & roots. Weekly Challenge. Series. Maths in STEM. Stage 5 - Reviewed 2012. Calculus generally. smartphone. Stage 5 - Core Mapping. Surds. Individual.
Published March 2003,April 2003.
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