对于直线m、 n 和平面 a、b、γ，有如下四个命题：（1）若,则,（2）若,,则,（3）若，，则，（4）若,则，其中正确的命题的个数是_刷题宝

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对于直线m、 n 和平面 a、b、γ，有如下四个命题：
（1）若 $\text{[math]}$ ,则 $\text{[math]}$ ,
（2）若 $\text{[math]}$ , $\text{[math]}$ ,则 $\text{[math]}$ ,
（3）若 $\text{[math]}$ ， $\text{[math]}$ ，则 $\text{[math]}$ ，
（4）若 $\text{[math]}$ ,则 $\text{[math]}$ ，
其中正确的命题的个数是（）

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:2019-06-03 03:44:01

答案(点此获取答案解析）

A

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