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【OG20-P278-291题】Is the integer x a 3-digit integer?
1. x is the square of an integer.
2. 90
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x是平方数,又因为大于90小于150,那么只能是100,121, 144.三个数都是三位数,所以结合两个条件可以推理得出,答案C
题目讨论 (4条评论)

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1048993hyug
求值时,答案要为一。如果求的是是不是符合这个条件,只有所有解都在这个条件下,就成立。
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0 回复 2022-10-15 21:05:19
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emily666
From (1) and (2) taken together, it follows that x is among the numbers ... , 81, 100, 121, 144, 169, ... and 90 < x < 150. Therefore, x must be one of the three numbers 100, 121, 144, and hence x must be a 3-digit integer. 看了OG,两个结合是充分的。
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0 回复 2020-04-05 23:01:23
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emily666
好吧,答案确定no也是sufficient!
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0 回复 2020-03-18 09:56:34
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emily666回复emily666
第三遍看懂了。。。答案是肯定的
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0 回复 2020-05-10 21:43:25
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emily666
不是选E吗??
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0 回复 2020-03-18 09:54:03