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设Sn是等差数列{an}前n项的和.已知与的等比中项为,与的等差中项为1.求等差数列{an...
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设S
n是等差数列{a
n}前n项的和.已知
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABgAAAAjCAYAAACOysqWAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAUVJREFU
SEvtVtsRwyAMoyuzDpswB1OwhGts3hAeSelXuMtdewELZEnkAzjEyeEATg5xsjixEwGsBikkaPtb
SAYwyvUBn1MAjALqBei0L1PRS1Ff3n+iiEzmfMCPMr3dWNAyzZHkSAN64szFqODiXJSH1XLJmIsA
fYUZpfAM47EI4OmRGnajahGASPE92Msrd9XE5ta/e4c3aiSEdsX8BJi0taq4wXP+y/vgoleuWCNb
ivcfATAleTHfixo13ik4P3vHFOVGKxaiPOm/k2nWq/ZIfl64V5JZEQAXR/lxob6TB3q3tpCvO3Wo
IWDw8s7tTAJoKAqVHI/b24/hkbKqBxD0fR8ghhQFZ8it0ge+2XmoPaWpMRpxeCNzio1kVLdOftSH
kFkpryoANtFunzk6gk/KMBTpq24vxFZ7Mw+71UoX816AKYFfHXHqbJJqP34AAAAASUVORK5CYII=
)
与
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABgAAAAjCAYAAACOysqWAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAATlJREFU
SEvtVtsNwyAMpCuzjjdhDqZgCYoxAcwjOGnoVyxFalXwxec7ux8fQu0MBNgZamfyyE4GcMZrpb1x
z0ISgAXsQ3h2ARCKhxdg0L5KRS9FY3n/iaJoMvQBPWBHb+O80eWMjo603iycKRwVlJySUjijRcYU
AowVZgFCDechBEj0aOOvjiohQCQl9eDavMJVk5vbfh4Vb+FMCP2NdQVh0raqogav+ef7YNIrTNbJ
No73hwCIkjpZ6sXYLN3Ybyiiy+VukGf8gjKtejVNjruLLy4GQNzOnCxYpbFf3DNsJ4MJ1mcVCJLm
I3W1RcoJIFADaKKWIjlAcfWgAgsH4k0AJuUWgP14B4BP2dqsqAV1OLN1cT055UT1/04WMr2Wmk7P
VERT/gcVHS+zHYBXvR52d1iq7rwASwK/utTlhr/XuMwAAAAASUVORK5CYII=
)
的等比中项为
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABgAAAAjCAYAAACOysqWAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAATpJREFU
SEvtVtsNxCAM41ZmHTZhDqZgCS4kHM8UUlTuq0iVKoXGYDtJPwGWOrkiwMmlTiZHdjKAt0ErHax/
FpIAnIk6wHMKgFCCeQEY+SoXvRTx9v4TRVhksQ7oMY47jQ9Wlz0aK9IFu6hMYaug5JSUlrdaVJhC
AN5hzhi4w3wJARI92oa7rUoIgKQkDe71qzhqsrj9O3d5Z2ZGGL9Y3wA6be8qEnjNfzsPLrSKyQbb
Ynt/CIAoqZMlLZhioZslypMhMkVcEGcEJoo2rbRiK/G3t6UiAUBww4JNKmfZcZtHJt8epPO5aiPd
QQGg7jEy4WawpFmplcamfVB6/n4f6pkoGeqgDu4CQCcMundRSfaA4BHg6gbFmtvnh9+sCw3w76gK
iiEmA0shX8tpJoYaNq6b3X5u/PIFWBL4Bb8y9BLksmGpAAAAAElFTkSuQmCC
)
,
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABgAAAAjCAYAAACOysqWAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAUVJREFU
SEvtVtsRwyAMoyuzDpswB1OwhGts3hAeSelXuMtdewELZEnkAzjEyeEATg5xsjixEwGsBikkaPtb
SAYwyvUBn1MAjALqBei0L1PRS1Ff3n+iiEzmfMCPMr3dWNAyzZHkSAN64szFqODiXJSH1XLJmIsA
fYUZpfAM47EI4OmRGnajahGASPE92Msrd9XE5ta/e4c3aiSEdsX8BJi0taq4wXP+y/vgoleuWCNb
ivcfATAleTHfixo13ik4P3vHFOVGKxaiPOm/k2nWq/ZIfl64V5JZEQAXR/lxob6TB3q3tpCvO3Wo
IWDw8s7tTAJoKAqVHI/b24/hkbKqBxD0fR8ghhQFZ8it0ge+2XmoPaWpMRpxeCNzio1kVLdOftSH
kFkpryoANtFunzk6gk/KMBTpq24vxFZ7Mw+71UoX816AKYFfHXHqbJJqP34AAAAASUVORK5CYII=
)
与
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABgAAAAjCAYAAACOysqWAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAATlJREFU
SEvtVtsNwyAMpCuzjjdhDqZgCYoxAcwjOGnoVyxFalXwxec7ux8fQu0MBNgZamfyyE4GcMZrpb1x
z0ISgAXsQ3h2ARCKhxdg0L5KRS9FY3n/iaJoMvQBPWBHb+O80eWMjo603iycKRwVlJySUjijRcYU
AowVZgFCDechBEj0aOOvjiohQCQl9eDavMJVk5vbfh4Vb+FMCP2NdQVh0raqogav+ef7YNIrTNbJ
No73hwCIkjpZ6sXYLN3Ybyiiy+VukGf8gjKtejVNjruLLy4GQNzOnCxYpbFf3DNsJ4MJ1mcVCJLm
I3W1RcoJIFADaKKWIjlAcfWgAgsH4k0AJuUWgP14B4BP2dqsqAV1OLN1cT055UT1/04WMr2Wmk7P
VERT/gcVHS+zHYBXvR52d1iq7rwASwK/utTlhr/XuMwAAAAASUVORK5CYII=
)
的等差中项为1.求等差数列{a
n}的通项a
n.
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