作者a1985526 (new)
看板GMAT
标题[计量] GWD 21-19
时间Tue Dec 4 11:51:29 2007
Q: The sequence a1,a2,...,an is such that an= 4*a(n-1) -3 for all integers n>1.
If a3=x, then a1=
A. 4x- 3
B. 16x-15
C. (x+3)/4
D. (x+3)/16
E. (x+15)/16
Ans: E
我选了C:
a3= 4a1-3 = x
所以a1 = (x+3)/4
how come the answer is E?!
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