Write the Lowest Rationalising Factor of : 7 - √7

Write the lowest rationalising factor of : 7 - √7

Sum

7 - √7
( 7 - √7 )( 7 + √7 ) = 49 - 7 = 42
Therefore, lowest rationalizing factor is ( 7 + √7 ).

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Rationalisation of Surds

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Chapter 1: Rational and Irrational Numbers - Exercise 1 (C) [Page 21]

Chapter 1 Rational and Irrational Numbers
Exercise 1 (C) | Q 2.4 | Page 21

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