👤
a fost răspuns

Calculati 3*(1+2+3+......+1000)+(3+4+5+......+1000)*(-3)

Răspuns :

Anutzaaaaaaaaaa
Aplicam cunoscuta formula SUMA LUI GAUSS:
3*(1+2+3+...+1000)+(3+4+5+...+1000)*(-3)=
3*([tex] \frac{1000*1001}{2} [/tex])+[(1+2+3+4+5+...+1000)*(-3)-(1+2)]=
3*(500*1001)+([tex] \frac{1000*1001}{2} [/tex]*(-3)-3]=
3*500500+[500*1001*(-3)-3]=
1501500+(-1501500-3)=
1501500+(-1501503)=
1501500-1501503=
-3

Alte intrebari