数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)在数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)求出{an},{bn}的通项公式后证明:1/(a1+b1

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数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)在数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)求出{an},{bn}的通项公式后证明:1/(a1+b1

数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)在数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)求出{an},{bn}的通项公式后证明:1/(a1+b1
数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)
在数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)
求出{an},{bn}的通项公式后证明:1/(a1+b1)+1/(a2+b2)+…1/(an+bn)<5/12

数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)在数列{an},{bn}中,a1=2,b1=4,且an,bn,an+1成等差数列,bn,an+1,bn+1成等比数列(n∈N*)求出{an},{bn}的通项公式后证明:1/(a1+b1
字数限制,我只讲思路:
通项:
①列举,猜出通项
②推导
③不会推导,数学归纳法证明猜想
an=n(n+1),bn=(n+1)²
证明:放缩法,关键:an+bn=(n+1)(2n+1)