Question

cate submultimi ordonate formate cu 2 elemente admite multimea A= {a,b,c.d} ?

Answer 1

[tex]Modul\ 1\\Aranjamente\ de\ 4\ elemente\ luate\ cate\ 2:\\ A^{2}_4=\frac{4!}{(4-2)!}=\frac{1*2*3*4}{1*2}=3*4=12\\Modul\ 2:\\Submultinile\ sunt:\\(a,b),(b,a),(a,c),(c,a),(a,d),(d,a),(b,c),(c,b),(b,d),(d,b),(c,d),(d,c)\\12\ submultini[/tex]