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Example 20 - Chapter 1 Class 9 Number Systems (Term 1)
Last updated at March 22, 2023 by Teachoo
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Example 20 Important You are here
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Transcript
Example 20 Rationalize the denominator of 1/(7 + 3√2 ). 1/(7 + 3√2 ) = 1/(7 + 3√2) × (𝟕 − 𝟑√𝟐)/(𝟕 − 𝟑√𝟐) = (7 − 3√2)/(7 + 3√2)(7 − 3√2) = (7 − 3√2)/((𝟕)^𝟐 − (𝟑√𝟐)^𝟐 ) = (7 − 3√2)/(49 − (3 × 3 × √2 × √2) ) = (7 − 3√2)/(49 − (9 × 2) ) ( As (a + b)(a – b) = a2 – b2 ) = (7 − 3√2)/(49 − 18) = (𝟕 − 𝟑√𝟐)/𝟑𝟏
