當(dāng)n=1時,
s2n=s2=3a1,
a2=s2-a1=2a1
q=2
a2^3=8
a2=2
a1=1
an=2^(n-1)
sn=2^n-1
=2x2^(n-1)-1
=2an -1
等比數(shù)列{an}的前n項和為Sn,若S2n=3(a1+a3+…+a2n-1),a1a2a3=8,則Sn與an的關(guān)系為
等比數(shù)列{an}的前n項和為Sn,若S2n=3(a1+a3+…+a2n-1),a1a2a3=8,則Sn與an的關(guān)系為
數(shù)學(xué)人氣:341 ℃時間:2019-09-29 03:24:17
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