SQUARE AND CUBE ROOT OF ANY NUMBER

If you want to find the root value of number you have to know some values


NO         SQUARE                 CUBE

1                      1                              1

2                      4                               8

3                      9                               27

4                     16                              64
 
5                      25                             125

6                      36                              216
  
7                      49                              343

8                      64                              512

9                      81                              729

10                   100                             1000

Eg:

9409
Split the number after two digit from right
94 / 09 
09 the number ending in 9 from the above square table
The last digit of square root may be 3 / 7
Come to 94 from above square table it's above 9

SQUARE OF NUMBER END WITH 5: 

The number near by 94 ending with 5 is 95
Easy to find the square of the number ending 5,Split the number 9/5 .First take 9 multiply to 
The next number so 9*10 is 90 is the fist two digits of square.
The 5 in 95'S square is 25 this is the last 2 digit the square .The 95's Square is 9025.
The answer may be 93/ 97 we know 95's square is 9025 more the 93 so the answer is 97 

Eg 2:

784
7/84
84 ending with 4 so 2/8.
7 it is more then 2^2 bun not 3^2 it exceed the given value so 2.
Answer may be 22/28.22's near by value ending with 5 is 25,it's square is 2*3=6,5*5=25(625)
625<784 so not 22 the answer is 28.

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