Q9 of 123 Page 3

Write the inverse of 5 under multiplication modulo 11 on the set {1, 2, …, 10}.

From the definition of multiplication modulo

a*b = (m is the base of the modulo)


Here the base is 11 and the set is {1,2,…,10}


So, we can make the composition table as :-



Thus, the identity element is 1.


So, the inverse of 5 is 9.


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