Răspuns:
Salut
Ex,11
a+b=7→(a=0;b=7),(a=1,b=6),(a=2;b=5)......(a=7;b=0);
Ex,12
a,b-b,a=1,1; a•b=1;b-a=1;
10b-a=1,→(a-1)-b=1, →a•b=2,
b=a•2; 10b-a=1; 10(a-2)-a=1; 9a=21; a≠N
≠nu apartine inseamna.
(a,b)€∅.(multime vida)
Ex,13
a)1,2+2,3+3,4+4+5,6+6,7+7,8=
3,5+3,4+4+5,6+6,7+7,8=
6,9+4+5,6+6,7+7,8=
10,9+5,6+6,7+7,8=
16,5+6,7+7,8=
23,2+7,8=
31.
b)1,23+2,34+3,45+5,55+6,66+7,77=
3,57+3,45+5,55+6,66+7,77=
7,02+5,55+6,66+7,77=
12,57+6,66+7,77=
19,23+7,77=
27.
Ex,1
a)32,1•10=321
b)62,37•100=6237
c)0,321•1000=321
d)1,468•10000=14680
==evergreen==
