👤
Cristinabranzan13
a fost răspuns

DAU CORONITA !!!
Aratati ca:
b) 111 I (abc+bca+cab)-bara deasupra la litere
c) 30^n I (5^n x6^n+15^n x2^n+1)
d)21 I (1+2+3+...+20)

^-puterea

Răspuns :

Gnocchi
b)abc+bca+cab=100a+10b+c+100b+10c+a+100c+10a+b=111a+111b+111c=111(a+b+c) divizibil cu 111
c)5^n *6^n+15^n *2^n=30^n+30^n=2*30^n divizibil cu 30^n
d)1+2+3+...+20=(1+20)*20/2=21*10=210 divizibil cu 21

Alte intrebari