Which of the following could be the units digit of 57^n, where n is a positive integer? Indicate all such digits A] 0 B] 1 C] 2 D] 3 E] 4 F] 5 G] 6 H] 7 I] 8 J] 9
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Which of the following could be the units digit of 57^n, where n is a positive integer? Indicate all such digits A] 0 B] 1 C] 2 D] 3 E] 4 F] 5 G] 6 H] 7 I] 8 J] 9
for all positive integers, so we can start changing the value of n from 1 upward
57^1= 5(7)
57^2= 324(9)
57^3= 18519(3)
57^4= 1055600(1)
57^5= 60169205(7)
57^6=...................(9)
If you keep increasing the power, the unit value which is in bracket will keep changing between 7,9,3 and 1 continuously hence the correct answer is B, D, H and J
Answer: 1(B), 3(D), 7(H) and 9(J)