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unit no

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unit no

by maihuna » Mon Apr 20, 2009 7:15 am
If x is an even no then x^4n where n is positive integer will have in unit place:

1. 0
2. 6
3. 4 & 6
4. 0 & 6
5. none
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by DeepakR » Mon Apr 20, 2009 8:24 am
x= 0,2,4,6 etc. Now when x=0 we get (x^4n)=0 Hence 0 is a unit digit.

Now when x=2 we get (x^4n)=16^n. When n=1 its 16 for n=2 its 256 and so on. Hence in this case we get 6 as units digit.

Hence answer is 0 and 6 = D.)

- Deepak
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