等差数列{an}中,已知a2+a3+a10+a11=36,则a5+a8=______.
人气:137 ℃ 时间:2020-01-27 03:13:37
解答
∵等差数列{an}中,已知a2+a3+a10+a11=36,根据等差数列性质,可得 a5+a8=a3+a10=a2+a11=36÷2=18,
故答案为 18.
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