Square Root
The square root of a number is the inverse operation of squaring a number. The square of a
number is the value that is obtained when we multiply the number by itself, while the
square root of a number is obtained by finding a number that when squared gives the
original number.
If 'a' is the square root of 'b', it means that a × a = b. The square of any number is always a
positive number, so every number has two square roots, one of a positive value, and one of
a negative value. For example, both 2 and -2 are square roots of 4. However, in most
places, only the positive value is written as the square root of a number.
What is Square Root?
The square root of a number is that factor of a number which when multiplied by itself
gives the original number. Squares and square roots are special exponents. Consider the
number 9. When 3 is multiplied by itself, it gives 9 as the product. This can be written as 3
× 3 or 32. Here, the exponent is 2, and we call it a square. Now when the exponent is 1/2, it
refers to the square root of the number. For example, √n = n1/2, where n is a positive
integer.
Square Root Definition
The square root of a number is the value of power 1/2 of that number. In other words, it is
the number whose product by itself gives the original number. It is represented using the
symbol '√ '. The square root symbol is called a radical, whereas the number under the
square root symbol is called the radicand.
How to Find Square Root?
To find the square root of a number, we just see by squaring which number would give the
actual number. It is very easy to find the square root of a number that is a perfect square.
Perfect squares are those positive numbers that can be expressed as the product of a number
by itself. In other words, perfect squares are numbers which are expressed as the value of
power 2 of any integer. We can use four methods to find the square root of numbers and
those methods are as follows:
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Repeated Subtraction Method
Prime Factorization Method
Estimation Method
Long Division Method
It should be noted that the first three methods can be conveniently used for perfect squares,
while the fourth method, i.e., the long division method can be used for any number whether
it is a perfect square or not.
Repeated Subtraction Method of Square Root
This is a very simple method. We subtract the consecutive odd numbers from the number
for which we are finding the square root, till we reach 0. The number of times we subtract
is the square root of the given number. This method works only for perfect square numbers.
Let us find the square root of 16 using this method.
1.
2.
3.
4.
16 - 1 = 15
15 - 3 =12
12 - 5 = 7
7- 7 = 0
You can observe that we have subtracted 4 times. Thus,√16 = 4