已知向量
a=(2,3),
b=(-1,2),若
a+
mb與
c=(4,-1)平行,則實數(shù)
m等于
A.2 | B.-2 | C. | D. |
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科目:高中數(shù)學
來源:不詳
題型:解答題
(本小題滿分12分)設向量
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=(3,1),
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=(-1,2),向量

垂直于向量

,向量

平行于
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,試求
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時,

的坐標.
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科目:高中數(shù)學
來源:不詳
題型:填空題
已知向量

若

,則
m=
.
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科目:高中數(shù)學
來源:不詳
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已知

,當實數(shù)

取何值時,
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
+2

與2

—4

平行?
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來源:不詳
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(本題滿分12分)已知
A(2,0),
B(0,2),
C(

),且0<

<

.
(1)若

的夾角;
(2)若

的值.
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來源:不詳
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已知

,則|

︱的取值范圍( )
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來源:不詳
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(本題滿分10分)已知平面內(nèi)三個向量:

.

.

(1)若

∥

,求實數(shù)

;
(2)若

⊥

,求實數(shù)

。
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
,則

的值為( )
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