已知等差數(shù)列{an}滿足a2+a4=4,a3+a5=10,則它的前10項(xiàng)的和S10=_.
已知等差數(shù)列{an}滿足a2+a4=4,a3+a5=10,則它的前10項(xiàng)的和S10=______.
優(yōu)質(zhì)解答
由a
2+a
4=4,a
3+a
5=10
得
可解得:
∴
s10=10a1 +×d=95故答案為:95
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