Răspuns :
Se considera S=3+5+7+...+77
S=3+5+7+...+77
S=77+...+7+5+3
----------------------
2S=80+80+...+80
Numar termeni : (77-3)/2+1=74/2+1=37+1=38
2S=80x38
S=80x38/2
S=40x38
S=1 520
Sper ca te-am ajutat ! :)
S=3+5+7+...+77
S=77+...+7+5+3
----------------------
2S=80+80+...+80
Numar termeni : (77-3)/2+1=74/2+1=37+1=38
2S=80x38
S=80x38/2
S=40x38
S=1 520
Sper ca te-am ajutat ! :)