1) a+b=42 ; a;b-nr.naturale
(a;b)=6 =>a=6m ∧ b=6n ; (m;n)=1
6m+6n=42 |:6
m+n= 7
se construieste un tabel si se dau valori
m n
0 7
1 6
2 5
3 4
4 3
5 2
6 1
7 0
1)m=0 =>a=6*0=0
n=7 =>b=6*7=42
2)m=1 =>a=6*1=6
n=6 =>b=6*6=36
3)m=2 =>a=6*2=12
n=5 =>b=6*5=30
4)m=3 =>a=6*3=18
n=4 =>b=6*4=24
5)m=4 =>a=6*4=24
n=3 =>b=6*3=18
6)m=5 =>a=6*5=30
n=2 =>b=6*2=12
7)m=6 =>a=6*6=36
n=1 =>b=6*1=6
8)m=7 =>a=6*7=42
n=0 =>b=6*0=0
S(x;y)={(0;42);(6;36);(12;30);(18;24);(24;18);(30;12);(36;6);(42;0)}
2)[a;b]=180
a*b=1 620
(a;b) * [a;b]= a*b
(a;b) *180=1 620
(a;b)= 1 620/180
(a;b)=9
