Question

Determinati multimile A si B , stiind ca sunt indeplinite simultan conditiile :
a ) A reunit B = { x apartine N | x mai mic sau egal 8 } ;
b ) A intersectat B = { 2 , 3 , 5 } ;
c ) A reunit { 2 , 5 , 6 } = { 0 , 1 , 2 , 3 , 5 , 6 , 7 } ;
d ) B reunit { 0 , 2 , 4 } = { 0 , 2 , 3 , 4 , 5 , 6 , 8 }

Answer 1

a) A U B = { x ∈ N / x ≤ 8}
   x ≤ 8  ⇒ x ∈ ( - 00, 8]
   x ∈ ( - 00. 8] ∧N ⇒ x ∈ { 0,1,2,3,4,5,6,7,8,}
   A U B = {1,2,3,4,5,6,7,8}
   A ={ 0,1,2,3,5,7}
   B = { 2,3,4,5,6,8}