Question

A 1/50+5/50+9/50+13/50+..........+41/50​

Answer 1

Răspuns:

$\frac{1}{50} (1 + 5 + 9 + 13 + .... + 41) =$

an=a1+(n-1)r==》an=1+(n-1)4=41===》

n-1=40/4=10

n=11

S=(a1+an)n/2=(1+41)×11/2=42×11/2=

21×11=231

Raspuns:231/50