Hi can anyone solve this question from ETS?
Only the unit digit plays a role in determining the unit digit of the result of the exponents. So we can we ignore everything else.
The question becomes how many possible values of unit digit can 4 raised to the power of x (4^x) take.
Solution:
4^1 = 4
4^2= 16
4^3= 64
4^4= 256
It’s evident that the unit digits will be a cycle of 4 and 6.
Therefore, number of possible values of unit digit is 2.
Okay got it. Thanks!
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