1) A= {2,3,5,7,11,13,17,19}
B= {10}
C= {8,9,10,11,12,13,14,15,16,17,18,19}
D= {1,4,9,16}
2) inverse de D= {2,3,5,6,7,8,10,11,12,13,14,15,17,18,19}
inverse de F= {1,2,6,7,8,10,12,13,14,15,18}
3) • {Ø}
• {11,16,17,19}
• {2,3,5,7,8,10,11,13,17,19}
• {3,4,5,8,9,10,11,12,13,14,15,16,17,18,19}
