题目
设有空集phi_(1),phi_(2)，记A为任一非空集合。根据集合的运算性质，下列结论成立的有（）.A. phi_(2)subseteq AB. phi_(2)in AC. phi_(2)in phi_(1)D. phi_(2)subseteq phi_(1)
设有空集$\phi_{1},\phi_{2}$，记A为任一非空集合。根据集合的运算性质，下列结论成立的有（）.
A. $\phi_{2}\subseteq A$
B. $\phi_{2}\in A$
C. $\phi_{2}\in \phi_{1}$
D. $\phi_{2}\subseteq \phi_{1}$
题目解答
答案
AD
A. $\phi_{2}\subseteq A$
D. $\phi_{2}\subseteq \phi_{1}$
A. $\phi_{2}\subseteq A$
D. $\phi_{2}\subseteq \phi_{1}$