- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How to find perfect square root?
There are two types of numbers:
Numbers which are a perfect square: Product of an integer with itself. For example, 9*9 = 81.
Numbers which are an imperfect square: Multiplying any number with itself. For example, 2.236*2.236 = 5.
Finding the square root of an imperfect square is a little more difficult than finding the square root of a perfect square number.
A perfect square cannot have 2, 3, 7, or 8 in the unit’s digit.
If a perfect square ends with a 1, then the unit’s digit of its square root has to be either 1 or 9.
If a perfect square ends with a 4, then the unit’s digit of its square root has to be either 2 or 8.
If a perfect square ends with a 5, then the unit’s digit of its square root is definitely 5.
If a perfect square ends with a 6, then the unit’s digit of its square root has to be either 4 or 6.
If a perfect square ends with a 9, then the unit’s digit of its square root has to be either 3 or 7
To find out the number of digits in the answer.
The square root of a number with an odd number of digits (for example, 24563 has 5 digits i.e. odd) will have (n+1)/2 digits in the answer (in our example, (5+1)/2 = 3 digits in the answer).
The square root of a number with an even number of digits (for example, 2456 has 4 digits i.e. even) will have n/2 digits in the answer (in our example, 4/2 = 2 digits in the answer).
There are two methods known as Division method and Prime factorisation method of finding the square root of a number.
Eg:
Let us find the square root of 441.
The prime factorization of 441 is 3 × 3 × 7 × 7.
Make the pair and select one factor from each pair that gives 3 × 7 = 21.
So, the square root of 441 = √441 = 21.