25、{x} denotes the greatest integer less than or equal to x. Is {x}=1?
(1)x>1
(2)x<2
【答案】C
【思路】{x}为X的整数部分
我觉得应是B答案呀,为何C?
题目:{x} 是指少于或等于x的最大整数,即{2.55}=2,{2}=2, {0.55}=0
(1) {2.55}=2 不充分
(2) {0.55}=0 不充分
(1)+(2): 1<x<2,充分
C
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