With this trick you can find the square of a number having only ‘1’ such as numbers are 11, 111, 1111 etc.
Short trick:
Write 1234… up to the number of 1′s in the given number first in ascending order then in descending order.
i.e. (1111……n times)2 = 1234….till n…..4321
Let’s understand it with the help of examples.
Let’s find the square of 111.
Solution:
Here, there are 3 ones in 111. Therefore n = 3.
So, (111)2 = 12321
Find the square of 1111.
Solution:
Here, there are 4 ones in 1111. Therefore n = 4.
So, (111)2 = 1234321
In the same way you can find the squares of numbers like 11111, 111111….etc.