Summarize this article:
955 LearnersLast updated on August 5, 2025

The square root is the inverse of squaring a number. 1.8 is not a perfect square. The square root of 1.8 is expressed in both radical and exponential form. In radical form, it is expressed as √1.8, whereas in exponential form it is expressed as (1.8)^(1/2). √1.8 ≈ 1.34164, which is an irrational number because it cannot be expressed in the form of p/q, where p and q are integers and q ≠ 0.
The prime factorization method is used for perfect square numbers. However, for non-perfect square numbers like 1.8, methods such as the long-division method and approximation method are used. Let us now learn the following methods:
The long division method is particularly used for non-perfect square numbers. Let us now learn how to find the square root using the long division method, step by step:
Step 1: Start with grouping the digits of 1.8. Since it has only one digit before the decimal, we treat it as 1.8.
Step 2: Now, find the largest number whose square is less than or equal to 1. The number is 1, as 1 × 1 = 1. Now, the quotient is 1, and after subtracting, the remainder is 0.
Step 3: Bring down 80 (since we add two zeros to the remainder after the decimal point). The new dividend is 80.
Step 4: Double the quotient and write it as the new divisor. So, 2 × 1 = 2.
Step 5: Find a digit n such that 2n × n is less than or equal to 80. Here, n = 3, since 23 × 3 = 69.
Step 6: Subtract 69 from 80. The remainder is 11.
Step 7: Bring down two zeros to make it 1100.
Step 8: The new divisor becomes 26. Find n such that 26n × n ≤ 1100. Here, n = 4, as 264 × 4 = 1056.
Step 9: Subtract 1056 from 1100. The remainder is 44. Step 10: Continue this process to get more decimal places.
The square root of 1.8 is approximately 1.34.


The approximation method is another technique for finding square roots. It is an easy method to estimate the square root of a given number. Let us learn how to find the square root of 1.8 using the approximation method.
Step 1: Find two perfect squares between which 1.8 falls. The closest perfect squares are 1 (1^2) and 4 (2^2). Therefore, √1.8 falls between 1 and 2.
Step 2: Apply the interpolation formula: (Given number - smaller perfect square) / (larger perfect square - smaller perfect square). For 1.8, the calculation is (1.8 - 1) / (4 - 1) = 0.8 / 3 ≈ 0.2667.
Step 3: Add this value to the smaller root: 1 + 0.2667 ≈ 1.267. Thus, the square root of 1.8 is approximately 1.34, when calculated more precisely.
Students often make mistakes while finding the square root, such as forgetting about the negative square root or misapplying methods like the long division method. Let us look at a few common mistakes in detail.
Can you help Max find the area of a square box if its side length is given as √1.8?
The area of the square is approximately 1.8 square units.
The area of a square = side^2.
The side length is given as √1.8.
Area = (√1.8)^2 = 1.8.
Therefore, the area of the square box is approximately 1.8 square units.
A square-shaped garden measuring 1.8 square meters is planned; if each of the sides is √1.8, what will be the square meters of half of the garden?
0.9 square meters.
Since the garden is square-shaped, we can divide the total area by 2 to find the area of half of it.
Dividing 1.8 by 2 gives 0.9.
So, half of the garden measures 0.9 square meters.
Calculate √1.8 x 3.
Approximately 4.025.
First, find the square root of 1.8, which is approximately 1.34164.
Then, multiply 1.34164 by 3.
1.34164 × 3 ≈ 4.025.
What will be the square root of (1 + 0.8)?
The square root is 1.34.
To find the square root, first find the sum of (1 + 0.8).
1 + 0.8 = 1.8.
The square root of 1.8 is approximately 1.34.
Find the perimeter of the rectangle if its length ‘l’ is √1.8 units and the width ‘w’ is 3 units.
The perimeter of the rectangle is approximately 8.68328 units.
Perimeter of the rectangle = 2 × (length + width).
Perimeter = 2 × (√1.8 + 3)
= 2 × (1.34164 + 3)
= 2 × 4.34164
= 8.68328 units.

Vikrant is a passionate Mathematics teacher with over 5 years of teaching experience in both conventional and Vedic Maths. His student-focused approach combines clear concepts with motivation and encouragement, helping students build confidence and develo
: He loves to play the quiz with kids through algebra to make kids love it.
We use cookies for essential site function, analytics, and marketing. You can accept all, reject non-essential cookies, or customize your choices. See our Cookie Policy.





