👤
a fost răspuns

Rezolva 3+6+9+12+............+33+36+39

Răspuns :

Alexandramaria2002
3+6+9+...+33+36+39=
=3(1+2+3+...+11+12+13)
=3×13×14:2
=39×14:2
=546:2
=273
39:3=13 termeni
3x(1+2++...13)=
3x13x14:2=
546:2=273


Alte intrebari