Question

Determinati n apartine N ,astfel incat (2n+3)|(5n+12)

Answer 1

Pai 2n+3/2n+3

2n+3/5n+12

Inmultim prima relatie cu 5 si a doua cu 2

2n+3/10n+15

2n+3/10n+24

Daca scadem obtinem ca:2n+3/9

2n+3=1 rezulta ca n=-1

2n+3=-1

2n=-4

n=-2

2n+3=3

n=0

2n+3=-3

n=-3

2n+3=9

2n=6

n=3

2n+3=-9

2n=-12

n=-6