Question
One’s digit of the number $(22)^23$ is
Answer: Option C
Answer: (c)Unit’s digit in the expansion of $(22)^23$= Unit’s digit in the expansion of $(2)^23$ Now, $2^1 = 2, 2^2 = 4, 2^3 = 8, 2^4 = 16, 2^5 = 32$i.e. 2 repeats itself after the index 4. On dividing 23 by 4, remainder = 3∴ Unit’s digit in $(2)^23$ = Unit’s digit in $(2)^3$ = 8
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Answer: (c)Unit’s digit in the expansion of $(22)^23$= Unit’s digit in the expansion of $(2)^23$ Now, $2^1 = 2, 2^2 = 4, 2^3 = 8, 2^4 = 16, 2^5 = 32$i.e. 2 repeats itself after the index 4. On dividing 23 by 4, remainder = 3∴ Unit’s digit in $(2)^23$ = Unit’s digit in $(2)^3$ = 8
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