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平面向量数量积的意义

> 在坐标平面上直线l的方向向量 e =(- 4 5 ， 3 5 )，点O（0，0），A（1，-2）在l上的正射影分别为O 1、A 1，设 O1A1 =λ e ，则实数λ=（　　） A．2 B．-2 C． 11 5 D．- 11 5

问题：

发布时间：2024-09-10

在坐标平面上直线l的方向向量

e

=(-

4

5

，

3

5

)，点O（0，0），A（1，-2）在l上的正射影分别为O ₁、A ₁，设

O1A1

=λ

e

，则实数λ=（　　）

A．2 B．-2 C．

11

5

D．-

11

5

参考答案：

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在坐标平面上直线l的方向向量 e =(- 4 5 ， 3 5 )，点O（0，0），A（1，-2）在l上的正射影分别为O 1、A 1，设 O1A1 =λ e ，则实数λ=（ ） A．2 B．-2 C． 11 5 D．- 11 5

可能感兴趣的题目：

在坐标平面上直线l的方向向量

e

=(-

4

5

，

3

5

)，点O（0，0），A（1，-2）在l上的正射影分别为O ₁、A ₁，设

O1A1

=λ

e

，则实数λ=（　　）

A．2 B．-2 C．

11

5

D．-

11

5