How To Find Square Root Of Numbers Easily Without Calculator
 |
| How to find square root ? |
Basic Information :
To find a square root of numbers first we have to some basic information. Such as, we have to know square of 1 to 30 numbers.
The second thing that we have to know which has unit digit 5. And we find these type of number's square easily. as....,
(5)2 = 25
(15)2 = 225
(25)2 = 625
(35)2 = 1225
(45)2 = 2025
(55)2 = 3025
………
Note the square of these numbers. The last number of square is always 25. And foreside number is the multiplication of the number excepting unit digit number and its ahead number.
i.e., (15)2 = (1 × 2)25
= 225
(25)2 = (2 × 3)25
= 625
(75)2 = (7 × 8)25
= 5625
(105)2 = (10 × 11)25
= 11025
The third thing we have to know is that
Unit number of question
|
Unit number of answer
|
1
|
1 or 9
|
4
|
2 or 8
|
9
|
3 or 7
|
5
|
5
|
6
|
4 or 6
|
Now we are able to find square root of numbers within a second. Let's understand it by example.
Method :
This method is applicable for perfect square numbers and mostly the question is asked about to find square root of perfect square numbers in competitive exam.
Example 1 : √6724
Step 1 :
First note the unit digit of given number and decide the unit digit of its answer.
i.e., Here the unit number of question is 4. So the unit number of answer will be 2 or 8.
Step 2 :
Now we will decide the ahead number of answer. Left last two digits of question always and see the remaining digits and note it that this number lies between whose square of numbers.
i.e., Here excepting last two digits of 6724 the remaining number is 67 ans this number lies between the square of 8 and 9. So the ahead number of answer will be 8. [ ∵ 8 < 9 ]
Thus, we have two numbers 82 and 88.
Step 3 :
Finally we have to decide which will be our answer 82 or 88.
85 lies between 82 and 88. And we know that (85)2 = 7225
∴ We have 6724 < 7225
∴ 82 will be our answer. [ ∵ 82 < 85 ]
Let's apply this method to another example.
Example 2 : √1296
Step 1 :
Here the unit number of question is 6. So the unit number of answer will be 4 or 6.
Step 2 :
Here excepting last two digits of 1296 the remaining number is 12 ans this number lies between the square of 3 and 4. So the ahead number of answer will be 3. [ ∵ 3 < 4 ]
Thus, we have two numbers 34 and 36.
Step 3 :
Finally we have to decide which will be our answer 34 or 36.
35 lies between 34 and 36. And we know that (35)2 = 1225
∴ We have 1296 > 1225
∴ 36 will be our answer. [ ∵ 36 > 35 ]
Now, you are able to find square root of perfect square number within a second without calculator. If you want to know Easy Method to Find Square of Number than click here.
No comments:
Post a Comment