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can you please tell an easy method to find the square root of large numbers

to find square root of 9801
1) divide it into pairs (98)(01)
2) divide first pair with square of number and take that number as quotient and bring next pair with remainder 9 |(98)(01)| 9
______________________________ -81
_______________________________1701
now taking double of quotient divide again byng nearest number next to it such that by multiplying final number by number obtained the product is less than equal to dividend 189|1701|99
_____________________________1701
_____________________________0


                                                      or
Factorise the large number that you are going to square root into prime numbers.

Such as, 144 = 6 (24) = 2 (3) (8) (3) = 2 (3) (2) (2) (2) (3)
= 2 (2) (2) (2) (3) (3)

Then, organise the factors into 2 groups of the same number of the same factors.

So, 144 = 2 (2) (2) (2) (3) (3) = (2*2*3) (2*2*3) = (2*2*3)^2

Hence, (square root 144) = [square root (2*2*3)^2] = (2*2*3) = 12
      
                                               or
A number ending in 25
________________

eg:-To find the square root of 1225

separate the digits other than  25
ie, 12      25
then multiply two consecitive numbers to get 12
ie, 3 and  4
take the smaller one ie,3
So the square root of  1225 is 35



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