如果2(x+3)的值与3(1-x)的值互为相反数,求x的值。
解:依题意得,2(x+3)+3(1-x)=0
解方程,得x=9
所以,x的值为9。
有关系模式A(C,T,H,R,S),其中各属性的含义是:C:课程T:教员H:上课时间R:教室S:学生根据语义有如下函数依赖集:F={C→T,(H,R)→C,(H,T)→R,(H,S)→R}现将关系模式A分解为两个关系模式A1(C,T)和A2(H,R,S),则其中A1的规范化程度达到( )。
A.1NF
B.2NF
C.3NF
D.BCNF
I feel sure that ______ qualification, ability and experience, you are abundantly suited to the position we have in mind.
A.in defence of
B.in spite of
C.in terms of
D.in favour of