3.Din (a,b)=14 => 14 | a si 14 | b => a=14x si b=14y (x,y∈N* ; (x,y)=1...adica sunt prime intre ele)
a+b=98
14x+14y=98
14(x+y)=98
x+y=7
x=1 => y=6 => a=14 si b=84
x=2 => y=5 => a=28 si b=70
x=3 => y=4 => a=42 si b=56
x=4 => y=3 => a=56 si b=42
x=5 => y=2 => a=70 si b=28
x=6 => y=1 => a=84 si b=14
Solutie: (a,b)∈{(14,84);(28,70);(42,56);(56,42);(70,28);(84,14)}
4.Stim ca relatia dintre c.m.m.m.c si c.m.m.d.c este: (a,b)*[a,b]=a*b, unde (a,b)=c.m.m.d.c, [a,b]=c.m.m.m.c, a*b= produsul.
Deci daca inlocuim vine (a,b)*385=2695=>(a,b)=2695/385=>(a,b)=7.
