an是等差数列,bn=1/2^an,已知b1+b2+b3=21/8,b1b2b3=1/8,求通向公式an,

an是等差数列,bn=1/2^an,已知b1+b2+b3=21/8,b1b2b3=1/8,求通向公式an, {an}是等差数列,bn={1/2}^an,已知b1+b2+b3=21/8,b1b2b3=1/8,(1)求an (2)求 设{an}是等差数列,bn=(1/2)^an,已知b1+b2+b3=21/8,b1b2b3=1/8,求an 高一数列习题{an}是等差数列,bn={1/2}^an,已知b1+b2+b3=21/8,b1b2b3=1/8,求an通项 设〔an〕是等差数列,bn=(0.5)an.已知b1+b2+b3=(21/8),b1b2b3=(1/8),求（an)的通 已知等差数列{an},设{bn}=1/2的an方 已知b1+b2+b3=21/8,b1b2b3=1/8,求{an} 设{an}是等差数列,bn={1/2}^an,已知b1+b2+b3=21/8,b1b2b3=1/8,证明{bn}是等比数 {an}是等差数列,bn={1/2}^an,已知b1+b2+b3=21/8,b1b2b3=1/8,证明{bn}是等比数列 设{an}是等差数列,bn=1/2^an,已知b1+b2+b3=21/8,b1*b2*b3=1/8,求等差数列的通项an 设数列{an}是等差数列,bn=(1/2)的an次方,又b1+b2+b3=21/8,b1b2b3=1/8,求通项an 设数列{an}是等差数列,bn=(1/2)的an次方,又b1+b2+b3=21/8,b1b2b3=1/8,证明数列｛bn 数列bn是等比数列,则b1+b2+b3=21/8,b1b2b3=1/8,数列an中,an=log2bn,求an的通项公式