题库搜索>问题求解PS-13630
The sequence ,
, … ,
, … is such that an =
- x for all positive integers n ≥ 2 and for certain number x. If
= 99 and
= 27, what is the value of x?
分析A选项
分析B选项
分析C选项
分析D选项
分析E选项
a5=2a4-x=99
a4=2a3-x=54-x
99=2(54-x)-x
x=3
166557rvym
an = 2an-1 - x
a5=2a4-x=2(2a3-x)-x=4a3-3x=99
a3=27
x=3
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