To find Square root,

we subtract consecutive odd numbers from number till we obtain 0.

 

Square root = Total numbers subtracted.

 

Let’s take an example

 

Suppose we need to find

√81

 

Square root of √81

  1. 81 − 1 = 80
  2. 80 − 3 = 77
  3. 77 − 5 = 72
  4. 72 − 7 = 65
  5. 65 − 9 = 56
  6. 56 − 11 = 45
  7. 45 − 13 = 32
  8. 32 − 15 = 17
  9. 17 − 17 = 0

Since, after subtracting 9 numbers, we obtained 0.

  ∴ 81   = 9

 

But, if we take a big number, like 729.

How would we find square root?

We do it by prime factorization  

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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 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.