list of possible last digit of squares.

Question

Does any one have a list of possible last digits of squares of numbers.
e.g 33^2
 123^2
 have the same last digit 9
 
I know there is a shortcut to such questions, I went through it in some. Cant seem to remember where though.

Thanks

bangalorian2000 · Answer

We take the unit digit of the number in this case 3 so
3^2 = 9 hence unit digit is 9.
In case number is something like this 123^234 then reduce it to 3^234,

3^1 = 3 unit digit is 3
3^2 = 9 unit digit is 9
3^3 =27 unit digit is 7
3^4 = 81 unit digit is 1
3^5 = 243 unit digit is 3
...
hence cyclicity is 4, after every power to 4 unit digit repeats hence dividing 234 by 4 we get 2 as remainder hence unit digit of 123^234 will be 9.

hb05sv · Answer

Thanks for the post. Here is a link for anyone who is looking for a list of cyclicity: https://takshzilabeta.com/index.php?opti ... -&Itemid=5

Hussain15 · Answer

This is a great link!!!

Kudos!!

ronny13 · Answer

pkumarbl · Answer

list of last digit of numbers which are not square can are given as 2,3,7,8 this can be used as one test to check if number is not square

list of possible last digit of squares.

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