Q15 of 114 Page 36

Give an example of two irrationals whose product is rational.

Let’s take (3 + ) and (3 ‒ ).

These are irrational numbers.


Their product = (3 + ) × (3 ‒ ) = 9 + 3√2 – 3√2 – (√2)2


= 9 – 4 = 5 {which is rational}


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