题干

已知△ABC的三边分别为x、y、z.

1)以 xyz 为三边的三角形一定存在;

2)以x2、y2、z2为三边的三角形一定存在;

3)以

1
2
(x+y)、
1
2
(y+z)、
1
2
(z+x)为三边的三角形一定存在;

4)以|x﹣y|+l、|y﹣z|+l、|z﹣x|+l为三边的三角形一定存在.

以上四个结论中,正确结论的个数为(    ).

A:1

B:2

C:3

D:4

上一题 下一题 0.0难度 选择题 更新时间:2014-06-26 09:20:54

答案(点此获取答案解析)

C

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