Q13:
If n is a positive integer, what is the remainder when 3^(8n+3) + 2 is divided by 5?
A. 0
B. 1
C. 2
D. 3
E. 4
waiting for your help.
solve promptly ?
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- hemanth28
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units digits of power of 3 are
3,9,7,1,3,9,7,1.....
so units digit is repetative in multiples of 4
so for 3^(8n+3) ,units digit =(units digit of 3^(8n)) * (units digit of 3^3)
=7
add 2 and divide by 5 gives reminder of 4.
3,9,7,1,3,9,7,1.....
so units digit is repetative in multiples of 4
so for 3^(8n+3) ,units digit =(units digit of 3^(8n)) * (units digit of 3^3)
=7
add 2 and divide by 5 gives reminder of 4.
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Thanks!
Please share your idea and your reasoning
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https://nguyensinguyen.vietnam21.org
https://bmnmed.com/home/
https://nguyensinguyen.vietnam21.org