Question

1.Aflati AxB,stiind ca:
a) (a;b)=20 si [a;b]=720
b) (a;b)=42 si [a;b]=210
c) (a;b)=18 si [a;b]=630

2.Aflati numerele a si b,stiind ca:
A) (a;b)=48 si [AxB]=144
B) [a;b]=144 si AxB=6912
C) (a;b)=15 si [AxB]=360
D) [a;b]=216 si (a;b)=18

Dau Coronita ;))

Answer 1

1.a) a x b = (a,b) x [ a , b ]
a x b = 20 x 720
a x b = 14400
b) axb=42x210
axb=2280
c) axb=18x630
axb=11340
2.a) nush
b) nush
c) nush
d)axb=216x18
axb=3888
a=18c
b=18d
18c x 18d =3888
18x18x(cxd)=3888
324x(cxd)=3888
cxd=12
(c,d)=1
cxd=1x12= 12x1= 3x4=4x3
primul caz :
c = 1 => a = 1x18=18
d=12=> b= 12x18 =216
al doilea caz :
c=12=>a=12x18=216
d=1=>b=1x18=18
al treilea caz :
c=3=>a=3x18=54
d=4=>b=4x18=72
al patrulea caz :
c=4=>a=4x18=72
d=3=>b=3x18=54