Perfect Square
A perfect square, also known as a square number, is an integer that is the square of another integer, meaning it is the product of some integer with itself. For example, 9 is a perfect square because it equals 3² and can be written as 3 × 3. In general, a perfect square can be expressed as x², where x is an integer. The first 20 perfect square numbers are 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225, 256, 289, 324, 361, and 400.
To identify a perfect square, one can look at the units place digit in its square number. For instance, numbers ending with 3 and 7 will have 9 as the units place digit in their square number, while numbers ending with 5 will have 5 as their units place digit in their square number. Additionally, all perfect squares end in 1, 4, 5, 6, 9, or 00 (even number of zeros) .
One way to check if a number is a perfect square is by finding its square root. If the square root is a whole number, then the number is a perfect square.
In summary, a perfect square is a number that can be expressed as the square of an integer, and it has specific characteristics that can help identify it, such as the units place digit in its square number and its square root property.
