Math, asked by amit55885, 1 year ago

what will be the unit digit of the square of the following number 12796

Answers

Answered by inhumandrowsey
13

Unit digit of square of 12796 will be 6


amit55885: explain sir
inhumandrowsey: 12796 X 12796 = 163737616 hence unit digit is 6
Answered by shadowsabers03
8

Unit digit of squares of numbers ending in 6 is always 6. So 6 is answer.


amit55885: explain sir
shadowsabers03: Let a number ending in 6 be 10x + 6.
shadowsabers03: (10x + 6)^2 = 100x^2 + 120x + 36 = 10(10x^2 + 12x) + 36.
shadowsabers03: Here, 10(10x^2 + 12x) ends in 0 as it is a multiple of 10. When 36 is added, the unit digit becomes 0 + 6 = 6. So the square of every number ending in 6 also ends in 6.
shadowsabers03: Also, 10x + 6 can be written decimally as x/6. (Not dividing)
shadowsabers03: 100x^2 + 120x = 36 = 100x^2 + 10 * 12x + 36. So it can be written decimally as x^2/12x/36 = x^2 = x^2 + x / 2x + 3 / 6. Here 6 comes at unit place.
Similar questions