Mentally Square of any number ending with 6.

Example, 1) 76^2

                Step 1) : Put 6 as it is.

                Step 2) :  Multiply 2 with (7 + 1) = 16 & add 16 + 1 = 17. Put down down 7 & add carry 1.

                Step 3) : Multiply 7 (with 7 + 1) = 56 + carry 1 = 57.... put down 57

So we get, 76^2 = 5776.

                2) 86^2

                Step 1) : Put 6 as it is.

                Step 2) :  Multiply 2 with (8 + 1) = 18 & add 18 + 1 = 19. Put down down 9 & add carry 1.

                Step 3) : Multiply 8 (with 8 + 1) = 72 + carry 1 = 73.... put down 73

So we get, 86^2 =7396.

                3) 46^2

                Step 1) : Put 6 as it is.

                Step 2) :  Multiply 2 with (4 + 1) = 10 & add 10 + 1 = 11. Put down down 1 & add carry 1.

                Step 3) : Multiply 4 (with 4 + 1) = 20 + carry 1 = 21.... put down 21

So we get, 46^2 =2116.

Best luck friends 😊 👍

"HAPPY HOLI"