Răspuns :
a) 1+2+3+4+...+50=
50X51 :2 sau supra 2 cum vrei. daca pui supra 2 se simplifica 50 cu 2 si ramane 25X51=1.275
50X51 :2 sau supra 2 cum vrei. daca pui supra 2 se simplifica 50 cu 2 si ramane 25X51=1.275
a) 1+2+...+50=51x50:2=51x25=1275
b)2(1+2+...+30)=2x30x31:2=930
c)3(1+2+...+33)=3x33xx34:2=1683
d)5(1+2+...+401)=5x401x402:2=404010
b)2(1+2+...+30)=2x30x31:2=930
c)3(1+2+...+33)=3x33xx34:2=1683
d)5(1+2+...+401)=5x401x402:2=404010