Răspuns:
Explicație pas cu pas:
Ex1. a) {1}, {2}, {1,2}, ∅
b) {2},{3},{5},{2,3},{2,5},{3,5},{2,3,5},∅.
c) {a},{b},{c},{a,b},{a.c},{b,c},{a,b,c},∅.
Ex5. A={0,1,2,3}, B={1,2,3,4}
pentru multimea A, avem 3x≤10
daca x=0, 3·0≤10, adevarat
daca x=1, 3·1≤10, adevarat
daca x=2, 3·2≤10, adevarat
daca x=3, 3·3≤10, adevarat
daca x=4, 3·4≤10, fals
deci A={0,1,2,3},
pentru multimea B, avem x+2<7
daca x=1, 1+2<7, adevarat
daca x=2, 2+2<7, adevarat
daca x=3, 3+2<7, adevarat
daca x=4, 4+2<7, adevarat
daca x=5, 5+2<7, fals
DECI B={1,2,3,4}
A⊄B, B⊄A
Ex6. A={4,5,6,7}, B={4,5,6,7}, C={4,5,6,7}, D={3,4,5,6,7,8,9}, E={0,2,4}.
A=B=C.
