a fost răspuns

daca a1+2+3...+11=a si9+10+11...+18 =atunci calculati a + b​

Răspuns :

Dianageorgiana794ask

Răspuns:

aplicam suma lui Gauss

1+2+3+..+n=[n·(n+1)]/2

1+2+3...+11=[11·(11+1)]/2=11·12:2=66

a=66

9+10+11...+18=(1+2+3+..+18)-(1+2+3+...+8)=(18·19)/2-(8·9)/2=171-36=135

b=135

a+b=66+135=>a+b=201

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