Let's say we want to get the square of 35 i,e 35 x 35,
Take the first no ie 3,take the next number i,e 4,
Multiply 3 and 4 ie 3 x 4 = 12,
Place 25 after 12,
So, the answer is 1225,
Lets try some more,
75 x 75 = (7x8) 25 = 5625,
25 x 25 = (2x3) 25 = 625,
Similar techniques for getting squares of any number, square roots, cube roots available.