Rationalisation of surds involves the multiplication of a surd by its conjugate to get a rational number. This process requires us to not leave the denominator in the surd form, but as a rational number.
Let’s consider . As per the definition of rationalisation of surds, we should have a rational number in the denominator, and not have a surd there. So we’ll multiply both the numerator and denominator by
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Examples of rationalisation of surds
Example 1:
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Example 2:
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Example 3:
= x
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= 4 + + 3
= 7 +
Example 4:
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