等差数列{an},a1,a2,a3,...,am的和为64,而且am-1 + a2=8,求m

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等差数列{an},a1,a2,a3,...,am的和为64,而且am-1 + a2=8,求m
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等差数列{an},a1,a2,a3,...,am的和为64,而且am-1 + a2=8,求m
等差数列{an},a1,a2,a3,...,am的和为64,而且am-1 + a2=8,求m

等差数列{an},a1,a2,a3,...,am的和为64,而且am-1 + a2=8,求m
由等差数列性质可得:
a1+am=a2+a(m-1)=8
而前m项和:Sm=m(a1+am)/2=64
那么:m*4=64
解得:m=16