数列{an}、{bn}满足a3=b3=6,a4=b4=4,a5=b5=3,且{a
题型:解答题
问题:
数列{an}、{bn}满足a3=b3=6,a4=b4=4,a5=b5=3,且{an+1-an}(n∈N*)是等差数列,{bn-2}(n∈N*)是等比数列.
(I)求数列{an}、{bn}的通项公式;
(II)n取何值时,an-bn取到最小正值?试证明你的结论.
数列{an}、{bn}满足a3=b3=6,a4=b4=4,a5=b5=3,且{an+1-an}(n∈N*)是等差数列,{bn-2}(n∈N*)是等比数列.
(I)求数列{an}、{bn}的通项公式;
(II)n取何值时,an-bn取到最小正值?试证明你的结论.