Даны множества: a={2,3,8}, b={2,3,8,11}, c={5,11} найдите: 1) aub, auc, buc, anb, anc, cnb

1) AuB {2,3,8,11}  
   AuC {2,3,5,8,11}   
 BuC {2,3,5,8,11}
 2) AnB{2,3,8} 
   AnC{...} 
   CnB{11}