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Question

The set {1, 2, 4, 7, 8, 11, 13, 14} is a group under multiplication modulo 15. The inverses of 4 and 7 are respectively

a.

3 and 13

b.

2 and 11

c.

4 and 13

d.

8 and 14

Answer: (c).4 and 13

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Q. The set {1, 2, 4, 7, 8, 11, 13, 14} is a group under multiplication modulo 15. The inverses of 4 and 7 are respectively

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