Question

a•) 2+5+8……+35
b•) 11+18+25+…+88
Va rog am nevoie urgenttt!!!

Answer 1

2+5+8…+35+5= 55
11+18+25…+88=88+18=142 n am fc bine stiu

Answer 2

a•) 2+5+8……+35=222

rația=5-2=3

an=a1+(n-1)r

S=(a1+an)n/2

35=2+(n-1)3

33=(n-1)3 /:3

n-1=11

n=12

S=(2+35)12/2=37×6=222

b•) 11+18+25+…+88=

r=18-11=7

88=11+(n-1)7

77=(n-1)7 /:7

11=n-1

n=12

S=(11+88)12/2=99×6=594