Tentukan invers dari 13 (mod 23)

23 = 1(13) + 10
13 = 1(10) + 3
10 = 3(3) + 1

1 = 10 - 3(3)
= 10 - 3(13 - 1(10))
= 4(10) - 3(13)
= 4(23 - 1(13)) - 3(13)
= 4(23) - 7(13)

1 = 4(23) - 7(13)
1 ≡ 4(23) - 7(13) (mod 23)
≡ -7.13 (mod 23)
≡16.13 (mod 23)

jadi, invers dari 13 (mod 23) = 16