等比数列复习(整理好的很详细)

3.31.{an}2..2.an=a1qn1an=amqnm.q=nmN*.3.nSn=q=.4.abcbacb=5.aaqaqaq3.6.1=2an+12=anan+2=.1.A.arccosB.arcsinC.arccosD.arcsinRtABCC=ABA.sin2B=sinAcos2A=sinA1sin2A=sinAsinA=sinA=.B2.{an}q=2a1a2a3a30=230a3a6a9a30A.210B.220C.216D.215a1a2a3=3a1a2a3a30=3.q=2a3a6a9a30=220.B3.20%5%A.5B.10C.14D.15120%n5%n13.4.n14.C4.200414{an}a3=3a10=384an=___________________.q7==128=27q=2.an=a3qn3=3n3.3n35.nnN*1___________________.111121133114641nnN*nCCCCn1nan=C+C++C=2n12.1n1a3+a4+an=2n2=2n2n.2n2n1{an}a1+a2+a3=7a1a2a3=8an.a1qa1q.{an}qan=2n1an=23n..a2q{an}2andanaaak11k25k317k1k2k3kn.akn.ana1aaaa14d2a1a116d.a12dq3.aa1kn1daa1n1kn2n11.k1k2kn2133n1n2n3nn1.knaknn.3{an}{bn}555lgbnlgan+1lgbn+1a1=1b1=2a2=3anbn.an+1=an=n.55552=52bn=an+an+1.lgbnlgan+1lgbn+12lgan+1=lgbn+lgbn+1an+12=bnbn+1.ai0bj0ijN*an+1=.an=n.2bn=+n2=+n.{}.b1=2a2=3a22=b1b2b2=.=+n1=n+1n=1.bn=.an===n.n=1a1=1.an=.Snana1S1.1.{an}an+12=anan+2.2.{an}ak2ak1ak+1kkNk.1.{an}q0nSnS8a9S9a8A.S8a9S9a8B.S8a9S9a8C.S8a9=S9a8D.nS8a9S9a8=a1q3a1q7===a12q7.q0S8a9S9a80S8a9S9a8.A2.rqqA.B.1+r31C.1+r31D.r1+r31+3qq1+r31.B3.20038a1q{an}na1qa1q=___________.|q|1nNa100q1.1a100q14.{an}1n+1an+12nan2+an+1an=0nN*an=___________________.n+1an+1nanan+1+an=0an0n+1an+1nan=0=.a1=1an=.5.*n11*1=12n+1*1=3n*1.n*1n.n*1n*1=ana1=1an+1=3anan=3n1n*1=3n1.6.{an}n54nSnSn=80S2n=65601100S100.2an.qS2nSn=6480Snq1.an=a1qn1an0.Sn==80S2n==6560a1=2q=31100S100==31001.2an=2n1.7.{an}nSn{bn}b1=a1bn=anan1nan+Sn=n.1cn=an1{cn}2{bn}.1a1=S1an+Sn=na1+S1=1a1=.an+1+Sn+1=n+12an+11=an1=={cn}.2c1=a11=cn=an=cn+1=1an1=1.nbn=anan1==.b1=a1=bn=nN*.8.anbnbn0n*ann*anbn.bnqanlgb1n1lgqan1anlgqan.annanlgb1lgb2lgbnn1an1lgb1lgb2lgbn1nan1anan1lgbn1.andnda1ndlgbn1bn110bn10.102d.bn.9.ana1a1a2anan1x2anx10n*n331.1:an2an3annSn.1331anan1.an.2a1ann1n.ann.3Sn++)++.1..2.q=1q.3.{an}1n2an2=an1an+1n.1..2.1a1annqSn2a10q1a100q1a10q1a100q1q0q=1.3..1{an}a1=1an=an1+1nan.an=an1+1an2=an12.bn=an2bn1=an12bn=bn1.bn=bn1=bn2=bn3=b1=n1b1.a1=1b1=a12=1.bn=n1.an=2.2{an}a1=a2=log2a2log2a3log2an+11a2a3an+1{an}.{log2an+1}an+1an{an+1}an+1an.an.{log2an+1}1log2an+1=log2a2a1+n11=log2n+1=n+1an+1=2n+1.{an+1an}an+1an=a2a1n1=n1=3n+1.an+1an=3n+1.an=2n+13n+1an=