Last updated on May 26th, 2025
If a number is multiplied by the same number, the result is a square. The inverse of the square is a square root. The square root is used in various fields such as vehicle design and finance. Here, we will discuss the square root of 42.
The square root is the inverse of the square of the number. 42 is not a perfect square. The square root of 42 is expressed in both radical and exponential form.
In the radical form, it is expressed as √42, whereas (42)^(1/2) in the exponential form. √42 ≈ 6.4807, 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, the prime factorization method is not used for non-perfect square numbers where long-division and approximation methods are used. Let us now learn the following methods:
The product of prime factors is the prime factorization of a number. Now let us look at how 42 is broken down into its prime factors.
Step 1: Finding the prime factors of 42 Breaking it down, we get 2 x 3 x 7.
Step 2: Now we found the prime factors of 42. The second step is to make pairs of those prime factors. Since 42 is not a perfect square, the digits of the number can’t be grouped in pairs. Therefore, calculating 42 using prime factorization is not exact.
The long division method is particularly used for non-perfect square numbers. In this method, we should check the closest perfect square number for the given number. Let us now learn how to find the square root using the long division method, step by step.
Step 1: To begin with, we need to group the numbers from right to left. In the case of 42, it is already a two-digit number, so we can consider it as 42.
Step 2: Now we need to find a number whose square is less than or equal to 42. We can say n as '6' because 6 x 6 = 36, which is less than 42. Now, the quotient is 6, and after subtracting 36 from 42, the remainder is 6.
Step 3: Add a decimal point to the quotient and bring down two zeros, making the new dividend 600.
Step 4: Double the current quotient to get 12, which will be part of our new divisor.
Step 5: Find a digit, let's say m, such that 12m x m is less than or equal to 600. Here, m is 4, since 124 x 4 = 496.
Step 6: Subtract 496 from 600, the difference is 104, and the quotient is 6.4.
Step 7: Continue this process to find more decimal places if needed.
So, the square root of √42 is approximately 6.48.
The approximation method is another method for finding square roots. It is an easy method to find the square root of a given number. Now let us learn how to find the square root of 42 using the approximation method.
Step 1: Now we have to find the closest perfect square of √42. The smallest perfect square less than 42 is 36 and the largest perfect square greater than 42 is 49. √42 falls somewhere between 6 and 7.
Step 2: Now we need to apply the formula: (Given number - smaller perfect square) / (larger perfect square - smaller perfect square) (42 - 36) / (49 - 36) = 6/13 ≈ 0.46
Using the formula, we determined the decimal part of our square root. The next step is adding the value we got initially to the decimal number: 6 + 0.46 ≈ 6.46.
Thus, the square root of 42 is approximately 6.46.
Students often make mistakes while finding the square root, such as forgetting about the negative square root or skipping steps in methods like long division. Let's look at a few of these mistakes in detail.
Can you help Max find the area of a square box if its side length is given as √42?
The area of the square is 42 square units.
The area of the square = side^2. The side length is given as √42.
Area of the square = side^2 = √42 x √42 = 42.
Therefore, the area of the square box is 42 square units.
A square-shaped building measuring 42 square feet is built; if each of the sides is √42, what will be the square feet of half of the building?
21 square feet
We can divide the given area by 2 since the building is square-shaped.
Dividing 42 by 2 = we get 21.
So half of the building measures 21 square feet.
Calculate √42 x 5.
Approximately 32.4
The first step is to find the square root of 42, which is approximately 6.48.
The second step is to multiply 6.48 by 5.
So 6.48 x 5 = approximately 32.4.
What will be the square root of (36 + 6)?
The square root is 6.
To find the square root, we need to find the sum of (36 + 6). 36 + 6 = 42, and then √42 = approximately 6.48.
Therefore, the square root of (36 + 6) is approximately ±6.48.
Find the perimeter of the rectangle if its length ‘l’ is √42 units and the width ‘w’ is 38 units.
We find the perimeter of the rectangle is approximately 88.96 units.
Perimeter of the rectangle = 2 × (length + width)
Perimeter = 2 × (√42 + 38) = 2 × (6.48 + 38) = 2 × 44.48 = approximately 88.96 units.
Jaskaran Singh Saluja is a math wizard with nearly three years of experience as a math teacher. His expertise is in algebra, so he can make algebra classes interesting by turning tricky equations into simple puzzles.
: He loves to play the quiz with kids through algebra to make kids love it.