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已知向量=(-1,3),=(x,-1)且,则x等于A.3B.C.-3D.
试题详情
已知向量
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAAWCAYAAAD0OH0aAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAACkSURBVDhP3VO5EQMhDFRdF6icy9UJsQpxSiEE
KmUt2RiOM3OMZxx4LCARu6sHQbi0grQnlAOGrgl+WxK2/dZg5Ib12ZBqmM8jfL+Gk+I6pX8nZHk9
oiBnAUl+63rtkkGZwGoVkCE+ARM8HoRQ7uDwhACj8YfhMwWzOuRgM1+9JlOeqJ8jdjEa03nmThTp
GHxPio7wbcS9O746aUZY/qAR8IPDdwc+xLsdewqvaAAAAABJRU5ErkJggg==
)
=(-1,3),
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAAWCAYAAAD0OH0aAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAACySURBVDhPrVO7EYUgEKQuA8oxv06Ir5CXUggB
pezjHsigHKBvZMbAYff2c2owPQFudwgNxswJ6TY4bPunwkw6WD8bXJF5rvB+hsvEtaURwVMJT37q
8qQQ2WKBR0OIYEuYz0dDiAy7Gp/MVoVsx4OORVpGVNIUgtiR0Iel/K4JZoJiR1obEvp2RMGCFU9J
QWnHE8ygANPZEXDN0qf+ZahbloaebHr5M7V7uAMWzP9f612FL960uYg38Ff7AAAAAElFTkSuQmCC
)
=(x,-1)且
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACUAAAAWCAYAAABHcFUAAAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAAElSURBVEhL7ZVLEoMgEETnXC44jntuwpqDZMtB
XHCUDuMHFZGh0LJMVahkkYRpHz09hFBcA0xvMJQ3Xfg1r0+i4mDQ9R9xW/OGjD6FBfndwTTaJWvz
8/f673TqNzPVHJb2Qrl97drNlfdAOQ1lfRHC6XmgtBNhH4NiEm8VKpjwIJSHVRqyT3gQyluoGpuC
ozunYt8pnCjkhCpFUJGpqXUOermslcVZCmcotpY2YZ2Ka5lkqEmf+LBjzKfPZ/ojFDu0nx4uUhAG
ap0iyalM6/iZ51BckFqZ+640yALUcerKhyYuOLqUOpcQcd6EP/LVhczUCXmlfeuWIHLrPMLr+kpb
Nx6ofDVQuNGg4ql58xbsOtOS2ehsxfTcc3newx5V/lC1hr7SqS+5975TCie62wAAAABJRU5ErkJg
gg==
)
,则x等于( )
A.3
B.
![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAgAAAAjCAYAAACpZEt+AAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAACWSURBVDhP3ZPLEcAgCESpjJ5sh2YshVKIiIkG
fxcnhzjDeMgGNo8NyObAQQGTIKAQv3vaiBgEAFLNBKaS8HNBhqQcrEKssE7uYrLW/Yjb2OjWpvsO
hxLVgmopmYcUFCSxpGloPEnm8tDcxLBCrdnsR9Q3M4uZIMuKWWyy34FiQoHH9Iik8+E6sBD6r3j+
qj5Nny5rsfMLN2zqeSiCl84AAAAASUVORK5CYII=
)
C.-3
D.
相关试题
-
已知向量
=(-1,3),
=(x,-1)且
,则x等于( )
A.3
B.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAgAAAAjCAYAAACpZEt+AAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAACWSURBVDhP3ZPLEcAgCESpjJ5sh2YshVKIiIkG
fxcnhzjDeMgGNo8NyObAQQGTIKAQv3vaiBgEAFLNBKaS8HNBhqQcrEKssE7uYrLW/Yjb2OjWpvsO
hxLVgmopmYcUFCSxpGloPEnm8tDcxLBCrdnsR9Q3M4uZIMuKWWyy34FiQoHH9Iik8+E6sBD6r3j+
qj5Nny5rsfMLN2zqeSiCl84AAAAASUVORK5CYII=
)
C.-3
D.
-
已知向量
与
的夹角为120°,
,则
等于( )
A.5
B.4
C.3
D.1
-
已知向量
与
的夹角为120°,
,则
等于( )
A.5
B.4
C.3
D.1
-
已知向量
=(-1,3),
=(x,-1)且
,则x等于( )
A.3
B.![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAgAAAAjCAYAAACpZEt+AAAAAXNSR0IArs4c6QAAAARnQU1BAACx
jwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAACWSURBVDhP3ZPLEcAgCESpjJ5sh2YshVKIiIkG
fxcnhzjDeMgGNo8NyObAQQGTIKAQv3vaiBgEAFLNBKaS8HNBhqQcrEKssE7uYrLW/Yjb2OjWpvsO
hxLVgmopmYcUFCSxpGloPEnm8tDcxLBCrdnsR9Q3M4uZIMuKWWyy34FiQoHH9Iik8+E6sBD6r3j+
qj5Nny5rsfMLN2zqeSiCl84AAAAASUVORK5CYII=
)
C.-3
D.
-
已知向量
与
的夹角为120°,
,则
等于( )
A.5
B.4
C.3
D.1
-
已知向量
和向量
的夹角为30°,|
|=2,|
|=
,则向量
和向量
的数量积
•
=( )
A.1
B.2
C.3
D.4
-
已知
,
是任意两个向量,下列条件:①
=
;②|
|=|
|;③
与
的方向相反;④
=
或
=
;⑤
与
都是单位向量,其中为向量
与
共线的充分不必要条件的个数是( )
A.1
B.2
C.3
D.4
-
已知下列各式:
①
;
②![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAH0AAAAWCAYAAADts5O8AAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
③![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAHcAAAAWCAYAAAD6kQN1AAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
④![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAHsAAAAWCAYAAADgreP7AAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
其中结果为零向量的个数为( )
A.1
B.2
C.3
D.4
-
已知下列各式:
①
;
②![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAH0AAAAWCAYAAADts5O8AAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
③![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAHcAAAAWCAYAAAD6kQN1AAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
④![](data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAHsAAAAWCAYAAADgreP7AAAAAXNSR0IArs4c6QAAAARnQU1BAACx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)
其中结果为零向量的个数为( )
A.1
B.2
C.3
D.4
-
已知向量
=(1,k),
=(2,2),且
+
与
共线,那么
•
的值为( )
A.1
B.2
C.3
D.4