Question 824201
when n is divided by 5 the remainder is 2 what is the remainder when square of n is divided by 5?
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n = 5k + 2 where k is an integer
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n^2 = 25k^2+20k+4
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Divide that by 5 to get:
n^2 = 5(5k^2+4k)+ 4/5
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Remainder = 4/5
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Cheers,
Stan H.
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