Salutare!
a) 128 și 180;
128 = 2⁷
180 = 2² × 3² × 5
c.m.m.d.c.(128;180) = 2² = 4
c.m.m.m.c.(128;180) = 2⁷ ×3² × 5 = 128 × 9 × 5
= 1152 × 5 = 5760
b) 420; 350 și 840
420 = 2² × 3 × 5 × 7
350 = 2 × 5² × 7
840 = 2³ × 3 × 5 × 7
c.m.m.d.c(420;350;840) = 2 × 5 × 7 = 10 × 7 = 70
c.m.m.m.c(420;350;840) = 2³ × 3 × 5² × 7 = 8 × 3 × 25 × 7
= 24 × 25 × 7 = 600 × 7 = 4200
c) 1600; 128 și 3240
1600 = 2⁶ × 5²
128 = 2⁷
3240 = 2³ × 3⁴ × 5
c.m.m.d.c.(1600;128;3240) = 2³ = 8
c.m.m.m.c.(1600;128;3240) = 2⁷ × 3⁴ × 5² = 128 × 81 × 25
= 10368 × 25 = 259200
d) 715 și 220
715 = 5 × 11 × 13
220 = 2² × 5 × 11
c.m.m.d.c.(715;220) = 5 × 11 = 55
c.m.m.m.c.(715;220) = 2² × 5 × 11 × 13 = 4 × 5 × 11 × 13
= 20 × 11 × 13 = 220 × 13 = 2860
