Rationalising denominator of irrational number

Last updated at April 16, 2024 by

Rationalising denominator of irrational number - Rationalising

We do not leave an irrational number in the denominator.

So, we rationalise the denominator.  Let us look at some examples

  1. Rationalise 1/√2
  2. Rationalise 1/2 +√3

Transcript

Some Identities (√𝑎)^2=𝑎 √(𝑎^2 )=𝑎 √𝑎𝑏=√𝑎 ×√𝑏 √(𝑎/𝑏)=√𝑎/√𝑏 (√𝑎−√𝑏)(√𝑎+√𝑏)=𝑎−𝑏 (𝑎−√𝑏)(𝑎+√𝑏)=𝑎^2−𝑏 (√𝑎+√𝑏)^2=𝑎+𝑏+2√𝑎𝑏 (√𝑎+√𝑏)(√𝑐+√𝑑)=√𝑎𝑐+√𝑎𝑑 + √𝑏𝑐 + √𝑏𝑑

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.