Maths Chapter 05: Squares and Square Roots

You know that the area of a square = side × side (where ‘side’ means ‘the length of a side’).

What is special about the numbers 4, 9, 25, 64 and other such numbers? Since, 4 can be expressed as 2 × 2 = 2² , 9 can be expressed as 3 × 3 = 3² , all such numbers can be expressed as the product of the number with itself. Such numbers like 1, 4, 9, 16, 25, ... are known as square numbers.

In general, if a natural number m can be expressed as n², where n is also a natural number, then m is a square number.

All square numbers end with 0, 1, 4, 5, 6 or 9 at units place. Square numbers can only have even number of zeros at the end.

Square root is the inverse operation of square.