§9.6 立体几何问题的 向量解法

1 / 16

# §9.6 立体几何问题的 向量解法 - PowerPoint PPT Presentation

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about '§9.6 立体几何问题的 向量解法' - taffy

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

§9.6立体几何问题的

1、平行

2、直线与平面垂直

A1

C1

B1

E

D

A

C

B

z

A1

C1

B1

D

C

A

y

B

x

z

A1

C1

B1

D

C

A

y

B

x

A1

C1

B1

D

A

C

B

z

D1

C1

A1

B1

D

C

G

y

A

F

B

x

E

1.证明线面平行的方法：

（1）线//线=›线//面

（2）共面向量定理

（3）法向量法

2.证明面面平行的方法：

（1）法向量法

（2）判定定理及推论

（二）用向量处理垂直问题

z

D1

C1

A1

F

B1

D

C

y

O

A

B

x

EFB1?并证明.

z

D1

C1

A1

B1

D

C

M

y

F

A

x

B

E

=∠BCD

B1

A1

(1)求证:C1C⊥BD

D1

C1

(2)当 CD/C1C 的值为多少时,能使A1C⊥平面C1BD.请证明.

B

A

C

D

|AB|=|AC|, ∠A1AB=∠A1AC.

C1

A1

B1

A

C

B

PA=PB,CA=CB.求证:

P

(1)PC⊥AB

E

F

(2)若PC=AB.E,F,G,H分别为PA,PB,BC,CA的中点,则GE⊥FH

C

H

A

G

B

1. 将逻辑推理(几何法)算法化 (代数法)是向量法的本质。

2.证明垂直问题的方法：