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已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+...
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已知{a
n}是递减等比数列,a
2=2,a
1+a
3=5,则a
1a
2+a
2a
3+…+a
na
n+1(n∈N
*)的取值范围是( )
A.[12,16)
B.[8,16)
C.
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
D.
相关试题
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是________.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAeFJREFU
WEfdl4GRhCAMRbmWaYdOrIMqaIIjIBA0BBZdwXVmZ3ZPOf8L+Qn5s+4Sb78A4u2XeDuAz6RpEGaz
UghIZSuULmVoFf4OH7lZ0xA5CUJblcS5705s4gC49CPcO0EeoOZAGFNEV6sMYbQu7plNNndjDgSO
JKTOMZ0+uT/VE+7lsAOkJxAE3qWaNebvxG5wuRH2LfxRd/d8CKeNzntjN6nsoW6RJEtAuLw6+UIr
aanNoSgcBBDvuenKGbmtX20m4f3Y27AzhdcdZPxNwSWIak7GpiP6I9Nkxs0M9whs9vReCDBOqzM0
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ZVxclr3RhlCuMvjqdZ+x0wm1MG+ukLX7JXX2bMPYWXg4IpTNJ77sYkgHl/dA+JzD0T8YHXJxj+Sg
iovLutIpnOVT/6hUJwCZc4G+HmPj6YvwxG0A3JRXi1BviX0mwsyUVxUAqdTV7J5BsMyURytgjh3R
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ANaA6FX6JmOPMM1PpxHVhzU/AfEPo3+gvtW+91sAAAAASUVORK5CYII=
)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAeFJREFU
WEfdl4GRhCAMRbmWaYdOrIMqaIIjIBA0BBZdwXVmZ3ZPOf8L+Qn5s+4Sb78A4u2XeDuAz6RpEGaz
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aanNoSgcBBDvuenKGbmtX20m4f3Y27AzhdcdZPxNwSWIak7GpiP6I9Nkxs0M9whs9vReCDBOqzM0
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ZVxclr3RhlCuMvjqdZ+x0wm1MG+ukLX7JXX2bMPYWXg4IpTNJ77sYkgHl/dA+JzD0T8YHXJxj+Sg
iovLutIpnOVT/6hUJwCZc4G+HmPj6YvwxG0A3JRXi1BviX0mwsyUVxUAqdTV7J5BsMyURytgjh3R
pM8fAIsJqDlPU013litPQe6Z8tad7LAybspjsnuZnYgaR07Ly0FQU16rxCwGca48LQC4Px+CmfJ6
ANaA6FX6JmOPMM1PpxHVhzU/AfEPo3+gvtW+91sAAAAASUVORK5CYII=
)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAeFJREFU
WEfdl4GRhCAMRbmWaYdOrIMqaIIjIBA0BBZdwXVmZ3ZPOf8L+Qn5s+4Sb78A4u2XeDuAz6RpEGaz
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)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAeFJREFU
WEfdl4GRhCAMRbmWaYdOrIMqaIIjIBA0BBZdwXVmZ3ZPOf8L+Qn5s+4Sb78A4u2XeDuAz6RpEGaz
UghIZSuULmVoFf4OH7lZ0xA5CUJblcS5705s4gC49CPcO0EeoOZAGFNEV6sMYbQu7plNNndjDgSO
JKTOMZ0+uT/VE+7lsAOkJxAE3qWaNebvxG5wuRH2LfxRd/d8CKeNzntjN6nsoW6RJEtAuLw6+UIr
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iovLutIpnOVT/6hUJwCZc4G+HmPj6YvwxG0A3JRXi1BviX0mwsyUVxUAqdTV7J5BsMyURytgjh3R
pM8fAIsJqDlPU013litPQe6Z8tad7LAybspjsnuZnYgaR07Ly0FQU16rxCwGca48LQC4Px+CmfJ6
ANaA6FX6JmOPMM1PpxHVhzU/AfEPo3+gvtW+91sAAAAASUVORK5CYII=
)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAgY0hSTQAAeiYAAICEAAD6AAAAgOgAAHUwAADqYAAAOpgAABdwnLpRPAAAAeFJREFU
WEfdl4GRhCAMRbmWaYdOrIMqaIIjIBA0BBZdwXVmZ3ZPOf8L+Qn5s+4Sb78A4u2XeDuAz6RpEGaz
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JKTOMZ0+uT/VE+7lsAOkJxAE3qWaNebvxG5wuRH2LfxRd/d8CKeNzntjN6nsoW6RJEtAuLw6+UIr
aanNoSgcBBDvuenKGbmtX20m4f3Y27AzhdcdZPxNwSWIak7GpiP6I9Nkxs0M9whs9vReCDBOqzM0
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pM8fAIsJqDlPU013litPQe6Z8tad7LAybspjsnuZnYgaR07Ly0FQU16rxCwGca48LQC4Px+CmfJ6
ANaA6FX6JmOPMM1PpxHVhzU/AfEPo3+gvtW+91sAAAAASUVORK5CYII=
)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
D.
-
已知{an}是递减等比数列,a2=2,a1+a3=5,则a1a2+a2a3+…+anan+1(n∈N*)的取值范围是( )
A.[12,16)
B.[8,16)
C.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADEAAAAjCAYAAAA9guKMAAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
D.