Question

a) b₁=2, n=7, bn=1458, Sn-? q-?

б) q=3, bn= 567, Sn=847, b₁-? n-?

в) b₁=½ , bn= 1/128, Sn= 127/128, q-? n-?

г) b₁= ⅓, q=1/3, bn=1/6561, n-? Sn-?

д) q= -3, n=4 , Sn=30, b1-? bn-?

ЛЮДИ ПОМОГИТЕ)

Answer 1

a) bn=b1q^n-1 => 1458=2q^6

q=3

Sn=b1(q^n-1)/(q-1)=2*2186/2=2186