Let “ ·n” be multiplication modulo n, and consider the set Un = { [a] ∈...

Let “ ·n” be multiplication modulo n, and consider the set Un = { [a] ∈ Zn | there is a [b] ∈ Zn with [a] ·n [b] = [1]}

(a) Show that (Un, ·n ) is a group.

(b) Write down the Cayley table for U5. Hint: |U5| = 4.

(c) Write down the Cayley table for U12. Hint: |U12| = 4.

Expert Solution

here i am using defination of group that is closed,associative ,identity and inverse .and remaining answers depends on group all answers are below thank you.

Colby Messinger answered 2 years ago

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