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3^12- last digit

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3^12- last digit

by ruplun » Wed Feb 29, 2012 7:25 am
What is the last digit of 3^12?

3 has a cycle of 4, hence 12 is divided by 4 , the remainder is 0 in this case.So what will be the last digit ..please let me know.
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by kmittal82 » Wed Feb 29, 2012 8:34 am
Not sure about the cycles method, but its quick enough to deduce

1 -> 3
2 -> 9
3 -> 7
4 -> 1
5 -> 3
...
...

Following this, power of 12 should give us a last digit of 1
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by neelgandham » Wed Feb 29, 2012 8:45 am
3^12 = (3^4)^3 = 81^3 = A1 (Where A is a positive integer).So,the unit's digit of 3^12 is 1
Anil Gandham
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