解(a1+a(2n+1))*(n+1)/2=44……①
(a2+a(2n))*n/2=33……②
①/②
(a1+a(2n+1))/2=(a2+a(2n))/2
化簡 n+1/n=44/33………項數(shù)為2n+1奇數(shù)項之和比上偶數(shù)項之和等于個數(shù)之比
解得n=3 共7項 中間項數(shù)為 4
項數(shù)為奇數(shù)項的等差數(shù)列,奇數(shù)項之和為44,偶數(shù)項之和為33,求此數(shù)列的中間項
項數(shù)為奇數(shù)項的等差數(shù)列,奇數(shù)項之和為44,偶數(shù)項之和為33,求此數(shù)列的中間項
數(shù)學人氣:841 ℃時間:2019-11-12 12:29:01
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