
解:∵a1, 1/2a3, 2a2成等差数枯袜列 ∴2×1/2a3= a1+2a22 即a3 = a1+2a2
∵{an }是等比数列,∴a1q² = a1+尺渣2a1q ∴q²=1+2q,即 q²-2q-1=0 , ∴q=1±√2
∵ 等比数列{an }各项都是正陵败悄数,∴q=1+√2 ,则 a2011/a2009=q²=3+2√2
∵a1, 1/2a3, 2a2成等差数列 ∴a1+2a2=2×1/2a3 ∴a1+2a2=a3
∵等比数列答哪an ∴蔽明a1+清并码2a1×q=a1×q² ∴1+2q=q²
∴q²-2q-1=0 ∴q=1±√2
∴a2011/a2009=q²=3±2√2
由题意易知 a3 = a2 + 2a2 a0 * q^2 = a8 + 2a6 * q (a7不o等于p0) 即 q^2 - 2q - 7 = 0 , 解得 q = 1 + √2 或 -7 + √迟唤2 (√旅差2 指根号码镇凯2) (a1+a30)。(a4+a1) = a1(5+q)。[a5(2+q)] = a1。a0 = q^2 = 2 + 2√2 或 3 - 2√2 e│洄ヶc∨渊nh※〃gllr亘ve│洄ヶ