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Question
For what value of natural number n, 4n can end with the digit 6?
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Solution
4n = (2 × 2)n = 2n × 2n
2 is a factor of 4n.
So, 4n is always even and ends with 4 and 6.
When n is an even number say 2, 4, 6, 8 then 4n can end with the digit 6.
Example:
42 = 16
43 = 64
44 = 256
45 = 1,024
46 = 4,096
47 = 16,384
48 = 65,536
49 = 262,144
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