# Rationalising Denominators

The start of the lesson reviews simplifying products and quotients involving surds since this is prerequisite knowledge for the remainder. In the development phase students are introduced to rationalising the denominator.  As learning progresses students are required to expand out a bracket using surds. The plenary challenges students to evaluate the areas of a rectangle and triangle where the dimensions are given with irrational fractions.
##### Differentiated Learning Objectives
• All students should be able to rationalise a denominator with a integer term as the numerator
• Most students should be able to rationalise a denominator with a surd as the numerator
• Some students should be able to rationalise a denominator with a integer and surd in the numerator

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