Question

Produsul a 2 nr . nat . =800

c.m.m.d.c lor = 20

c.m.m.m.c = ?

Answer 1

a∈N
b∈N
(a,b)=20
a=20m
a=20n
(m,n)=1
m∈N
n∈N
a*b=800
(20m)*(20n)=800
400mn=800
mn=800:400
mn=2
Avem 2 solutii
m=1 n=2
n=2 m=1
De asemenea:
a=20 b=40
b=40 a=20
20=2^2*5
40=2^3*5
cmmmc(20,40)=2^3*5=40