设数列{an}满足:若n=2k-1,(k∈N*)an=n;若n=2k,(k∈N*),an=ak求(1)a2+a4+a6+a8+a10+a12+a14+a16(1)原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+a5+a3+a7+a1=4a1+2a3+a5+a7=4×1+2×3+5+7=22想知道原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+
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![设数列{an}满足:若n=2k-1,(k∈N*)an=n;若n=2k,(k∈N*),an=ak求(1)a2+a4+a6+a8+a10+a12+a14+a16(1)原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+a5+a3+a7+a1=4a1+2a3+a5+a7=4×1+2×3+5+7=22想知道原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+](/uploads/image/z/7143804-36-4.jpg?t=%E8%AE%BE%E6%95%B0%E5%88%97%7Ban%7D%E6%BB%A1%E8%B6%B3%EF%BC%9A%E8%8B%A5n%3D2k-1%2C%28k%E2%88%88N%2A%EF%BC%89an%3Dn%3B%E8%8B%A5n%3D2k%2C%28k%E2%88%88N%2A%EF%BC%89%2Can%EF%BC%9Dak%E6%B1%82%281%29a2%2Ba4%2Ba6%2Ba8%2Ba10%2Ba12%2Ba14%2Ba16%EF%BC%881%EF%BC%89%E5%8E%9F%E5%BC%8F%3Da1%2Ba2%2Ba3%2Ba4%2Ba5%2Ba6%2Ba7%2Ba8%3Da1%2Ba1%2Ba3%2Ba1%2Ba5%2Ba3%2Ba7%2Ba1%3D4a1%2B2a3%2Ba5%2Ba7%3D4%C3%971%2B2%C3%973%2B5%2B7%3D22%E6%83%B3%E7%9F%A5%E9%81%93%E5%8E%9F%E5%BC%8F%3Da1%2Ba2%2Ba3%2Ba4%2Ba5%2Ba6%2Ba7%2Ba8%3Da1%2Ba1%2Ba3%2Ba1%2B)
设数列{an}满足:若n=2k-1,(k∈N*)an=n;若n=2k,(k∈N*),an=ak求(1)a2+a4+a6+a8+a10+a12+a14+a16(1)原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+a5+a3+a7+a1=4a1+2a3+a5+a7=4×1+2×3+5+7=22想知道原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+
设数列{an}满足:若n=2k-1,(k∈N*)an=n;若n=2k,(k∈N*),an=ak求(1)a2+a4+a6+a8+a10+a12+a14+a16
(1)原式=a1+a2+a3+a4+a5+a6+a7+a8
=a1+a1+a3+a1+a5+a3+a7+a1
=4a1+2a3+a5+a7
=4×1+2×3+5+7
=22
想知道原式=a1+a2+a3+a4+a5+a6+a7+a8
=a1+a1+a3+a1+a5+a3+a7+a1
是如何得出的
设数列{an}满足:若n=2k-1,(k∈N*)an=n;若n=2k,(k∈N*),an=ak求(1)a2+a4+a6+a8+a10+a12+a14+a16(1)原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+a5+a3+a7+a1=4a1+2a3+a5+a7=4×1+2×3+5+7=22想知道原式=a1+a2+a3+a4+a5+a6+a7+a8=a1+a1+a3+a1+
n=2k-1就是说这是奇数项,2k就是偶数项
奇数项等于它本身
偶数项举个例子吧,比如最后那个8
根据an=ak,n=2k可以知道 a8=a4,然后再进一步a4=a2=a1
4399弹弹堂全区 原定于7月23日(星期二)10:10~11:10进行的更新维护,由于数据量大,故维护时间将延时7月23日(星期二)10:10~13:00,具体完成时间将视维护工作