Question

Fie multimea A={1,x,2,3} Determinati valoarea lui x stiind ca: A U {1,2,3,4,5,6}={1,2,3,4,5,6,7}

Answer 1

A={1; x; 2; 3}
A∪{1; 2; 3; 4; 5; 6}={1; 2; 3; 4; 5; 6; 7}  ⇒     x=7