Question

using a suitable pattern find the square of 1111111 and also show that the sum of the digits of the square so obtained is also a perfect square.​

Answer 1

$\\ {1 }^{2} = 1 \\ {11}^{2} = 121 \\ {111 }^{2} = 12321 \\ ..................... \\ {1111111 }^{2} = 1234567654321$