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已知等差数列{an}的前n项和为Sn,且S10=12,则a5+a6=A.B.12C.6D.
试题详情
已知等差数列{a
n}的前n项和为S
n,且S
10=12,则a
5+a
6=( )
A.
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAA8AAAAjCAYAAABLuFAHAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAADaSURBVEhL1ZThEYYgCIaZzJ1Yx2UYxVH4RNNE
xazvT713dkf6BBIA/IfeAAfPDhz7cNhFhAwAeTnP7XaG64EOlg8iHQYxyplqq7BlU8OBSHkK3inv
S3iQRLjruRchcMPegNX9szbhwN5hPKG1BRPO31/CkmEVbUxasTOcCuQohLjKpiSoFkhdZ/iN5/v6
KjwmZG8lOD0f6oVw6t1yx26CFBlwLFUDaDWHm/pdaQJL+5VfMrZhq2XCcmPYA2IJi1LijDtcwqvk
7cFPPVsjSDTCxlSZaSNsW5+EmX8sB3dKMd0ZvgAAAABJRU5ErkJggg==
)
B.12
C.6
D.
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