Question

Bn-геометрическая прогрессия b1=6, q=2 найти s5

Answer 1

Sn=b1*(g^n-1)/q-1
S5=6*(2^5-1)/1=192-6/1=186

Answer 2

S(5)=b1*(qñ-1)/(q-1)=6*(2^5-1)/(2-1)=

6*31=186