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| How To Find Square Root | Rhinedealsd |
How To Find Square Root
Well, here I am not going to talk about the usual method on how to find the square root but I will tell you the trick that you can use to figure out the square root of any number in just seconds!!
The technique is very much helpful for the people to answer the time bound MCQ questions accurately in no time. So lets begin...
Before we start, lets brush -up the basics.
To calculate the square root of any perfect square number you need to first understand & remember some basic squares.
Square of 1 (1^2)= 1
Square of 2 (2^2)= 4
Square of 3 (3^2)= 9
Square of 4 (4^2)=16
Square of 5 (5^2)= 25
Square of 6 (6^2)= 36
Square of 7 (7^2)= 49
Square of 8 (8^2)= 64
Square of 9 (9^2)=81
Here note that the last digit of the outcome.
e.g -
when the last digit is 1 it is square root of either 1 or 7.
when the last digit is 4 it is square root of either 2 or 8.
when the last digit is 9 it is square root of either 3 or 7.
when the last digit is 6 it is square root of either 4 or 6.
This is all about basics. Now lets get into the method of finding the square root of any number.
Say you have to find out the square root for 1089 and the question in MCQ will be as shown below. So lets see how you can find it out.
Q. What is the square root of 1089
Option A. 33
Option B. 35
Option C. 28
Option D. 38
Step 1. Define the range of the number. Here the 1089 lies between the square of 30(30^2 = 900) and 40(40^2 = 1600)
Step 2. Look at the last digit. Its 9.
Step 3. Recall that when 9 is last digit it comes either from 3 or 7.
Step 4. Since you already know the range and last digit of it , square root o 1089 can be either 33 or 37. But if you look close enough, you will find 1089 is very close to 30, so the closest number to 30 is 33. Hence the square root of 1089 is 33 (Option A).
Remember this only works for the number which are perfect square and generally in MCQ the perfect square number they ask.
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