Vector 3 Axis
description
Transcript of Vector 3 Axis
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3.1
YY
X
X Z
Z
XX , YY , ZZ X Y Z O X Y Z ( Origin ) P 3 P P ( x , y , z ) P(3,4,4) XY , YZ XZ P(3,4,4) (QR,RS QS)
X
Y
Z
P 3,4,4
R
Q
S
P(3,4,4) XY Q 3,4,0 YZ R(0,4,4) XZ S(3,0,4)
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1 1 1P(x , y ,z ) 2 2 2Q(x , y ,z )
2 2 22 1 2 1 2 1PQ x x y y z z
2 2 2QR 0 3 4 4 4 0
9 0 16 25 5 2 2 2RS 3 0 0 4 4 4
9 16 0 25 5 2 2 2QS 3 3 0 4 4 0
0 16 16 32 4 2
3.2
(1) (Scalar Quantity) (2) (vector quantity ) A B
A
B
A B
A
B
ABAB
AB
AB AB
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AB A B A B AB AB A B A B () AB AB AB
u u
A
B
A B
A
B
u
u
u
u
u u v u v
u
v
w
u
v
w
u
v
w
u v u v u v u = v
u
v
w
u
v
w
u
v
w
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u u u u - u
u
u v
v
w
w
1 10 (1) 50 009 (2) 65 040 (3) 30 150 (4) 40 300 0o 360o 100o three figure system
OA 50 009 OB 65 040 OC 30 150 OD 40 300
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( 0o 360o 100o three figure system ) (1) 120 (2) 30 120o (3) 60 225o (4) 10 075o
N
120
A
B
N
A
B
120
30
N
A
B
225
60
N
A
B75
10
1 2 3 4
5 5 50
v,u,w vuw v
u w u w v
u
w v
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A
B
CS
AB BC AC
AB BC
AC
P
QR
RS
QR
PQ
PS
PQ QR RS PS
(jew vector) 0 AB BC CA AA 0
A
B
C
AB BC CA AA 0
AB BC
CA
PQ QR RS SP PP 0
SP
QR
RS
QR
PQ
SP
PQ QR RS SP PP 0 v,u )v(uvu
vu u v
u
v
u
v
u v
u
2u
2u
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2 u 2 u u ( -2 u ) 2u u 1 u a ( ) u a a u
1. a = 0 a u = 0 2. a > 0 a u a u
u 3. a < 0 a u a u
u
1 u v , a b
1. a u 2. a(b u ) = (ab) u 3. a( u + v ) = a u + a v 4. (a+b) u = a u + b u
2 0u 0v u v a
vau 3 0u 0v , u v Rb,a
0vbua a = 0 b = 0
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PQ u,v,w
u
v
P
Q
1
u
v
w
P
Q 2 PQ u v PQ u v w
u
v
wP
Q 3 P
Q
u
w
v
4 PQ u v w PQ u v w ( ) 1. 1.1 () - A B B C AC P Q Q R R S PS
A
B
CS
AB BC AC
AB BC
AC
A B B C AC
P
QR
RS
QR
PQ
PS
PQ QR RS PS
P Q Q R R S PS
- OB OC BC
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1.2 AB CB A B B C AC 1 1. A B B C AC
2. A B B C C D AD
3. A B B C C D D E AE 4. AB BC CD DE EA AA 0 2 () 1. AB CB AC 2. AB CB CD AD 3. AB BC DC AD 4. AB CB CD ED EA AA 0 3 () 1. OB OA AB 2. OC OB BC 3. AC AB BC 4. EC ED DC 4 . AB , BD , CA , DB , AF , FA , AE EA a, b, c, d, e f
A
B C
D
E
F
a
b
c
e
c
d
f
AB a BD b c a f CA b a c f
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DB b c f a DB b c f a AF f e a b c e f c d FA f e e a b c f c d AE f c a b 2c f e d EA f c a b 2c f e d 5. u
u
1. 2u 2. 3u 3. 0u
1 2u 2 3u 3 0
C AB
O
m n
vu
w
nu mvwm n
2 2B x , y 1 1A x , y
m n
C x, y
2 1mx nxx
m n
2 1my nyym n
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1. w u v
u v
w
2 3
1
vu
w
1 4
2
3u 2v 3u 2v
w3 2 5 5
4u 1v 4u vw
4 1 5 5
vu
2 5
3
w
u
w
v
1 3
4
5u 2v 5u 2v
w5 2 7 7
3u 1v 3u vw
3 1 4 4
2. ABCD A 1,2 AB 9 i 4 j, AD i 5 j C 1. 7,11 2. 8,11 3. 9,11 4. 8,9
A 1,2 B
C a,bD
AB 9 i 4 j
AD i 5 j AC
AC AB AD AC 1 9 i 5 4 j 8i 9 j
C a,b a 1 89b 2
a 1 8 a 7 b 2 9 b 11 7,11
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3. ABCD P Q AB AQ:QB 2:3 u AB v AD PQ
1. 1 u 3v6
2. 1 7u 3v6
3. 1 u v10
4. 1 u 5v10
u AB v AD
BA
CD
u
v
32
P
Q
1 2
PQ CA AB2 5
1 2
AC u2 5
1 2u v u
2 5
1 1u v10 2
1u 5v
10
4. ABC E CE 2BA BE aCB bCA a,b b a 1. -1 2. 2 3. 3 4. 5
CE 2BA BE aCB bCA
BE BC CE CB 2BA CB 2 BC CA CB 2 CB CA CB 2CB 2CA 3CB 2CA a 3,b 2 b a 2 3 5
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5. ABCD M, N BC CD u AM v AN AB
1. 3 1u v2 2
2. 3 u v2
3. 2 1u v3 2
4. 4 2u v3 3
ABCD M, N BC CD u AM v AN
A B
CD
u
v M
N
AB u MB..... 1 AB v NC CB
1AB v AB 2MB2
1 1MB AB v...... 24 2
(2) (1)
1 1
AB u AB v4 2
1 1
AB AB u v4 2
3 1AB u v4 2
4 2AB u v3 3
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6. AB P AB AB C PA,PC PB
P
AC
B
1. PC 4 PA PB 2. PC 2 PA PB 3. 2PC PA PB 4. 4PC PA PB 5. 1. 4.
P
AC
B1 1
PBPA
1PB 1PBPC
1 1
2PC PA PB 3. 7 . [ . / 2551] ABCD M N BC CD
BM:MC = DN:NC =1:2 AC AM AN
A B
CD N
M
1 2
2
1
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A
CD N1 2
1
A B
C
M
2
1
2
2AD 1ACAN
2 1
2AB 1ACAM
2 1
3AN 2AD 1AC .... 1 3AM 2AB 1AC .... 2 1 2
3AN 3AM 2AC 2AB 2AD 3AN 3AM 2AC 2 AB AD BC AD
3AN 3AM 2AC 2 AC
3AN 3AM 4AC
3 3AN AM AC4 4
3 3 6 1.54 4 4
8. ABCD M AD 1AM AD5
N AC 1AN AC6
MN aAB bAD a b
1. 215
2. 15
3. 13
4. 1
A
B
CD
11
4
5M
N
1AM AD
5 1AN AC
6
MN AN AM
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1 1AC AD6 5
1 1AB AD AD6 5
1 1aAB bAD AB AD6 30
1 1 2a b6 30 15
9. ABC D AC F BC 1 1
AD AC , BF BC4 3
DF aAB bBC ab
A
D
CB F
1
1 2
3
DF DC CF
3 2 3 2AC CB AB BC BC4 3 4 3
3 3 2AB BC BC4 4 3
3 1AB BC aAB bBC4 12
a 3 12 9b 4 9
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10. A a,b ,B 4, 6 C 1, 4 ABC P
AB A 35 A B CP i 2 j
a b
C 1, 4
A a , b
B 4 , 6
P x , y
3
2
C P i 2 j
2 2B x , y 1 1A x , y
m n
C x, y
2 1mx nxx
m n
2 1my nyym n
x 1 1
CPy 4 2
2a 12 25
2b 18 2
5
x 1 1y 4 2
2a 12 10 2b 18 10
x 2, y 2 a 1 b 4
a b 1 4 3
11. ABCD M AD 1AM AD5
N AC 1AN AC6
MN aAB bAD a b
1. 215
2. 15
3. 13
4. 1
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A
B
CD
11
4
5M
N
1AM AD
5 1AN AC
6
MN AN AM
1 1AC AD6 5
1 1AB AD AD6 5
1 1aAB bAD AB AD6 30
1 1 2a b6 30 15
12. u v PR 3u 1. QR 2. PS 3. SQ
uv
P
Q
R
S 1. QR 2u 2. PS 3u v 3. SQ 2u v 13. ABC AD BA a BD b CA
A
B CD
a
b 1. a 2. a b 3. a 2b 4. a 2b ( 3)
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2 u v 1. u v u kv k 1.1 k 0 1.2 k 0 1.3 k 0 2. u v au bv a 0 b 0
1. u 0 v 0 x u v
1.1 2 22x x u v xv 6x 2 x u u v
2 22x x u v xv 6x 2 x u
2 22x x u 6x 2 x u xv v
23x 7x 2 u x 1 v
2
x 1u v
3x 7x 2
u v
2
x 10
3x 7x 2
x 10
3x 1 x 2
1
1
32
1x , 1 ,23
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1.2 2x 1 u 3v v 5 x u u v
2x 1 u 3v v 5 x u
2x 1 u 5 x u v 3v
2x x 6 u 2v
2
2u v
x x 6
2
20
x x 6
2x x 6 0 x 2 x 3 0 x 3,2
1.3 22x 8 u xv 3v x u u v
22x 8 u xv 3v x u
22x 8 u x u 3v xv
22x 8 x u 3 x v
2
3 xu v
2x 8 x
u v
2
3 x0
2x 8 x
2
x 30
x 2x 8
x 30
x 4 x 2
2 3 4
x , 3 3,4
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3.3 . AB 1 2A(x , y ) 2 2B(x , y )
AB 2 12 1
x x
y y
2 1x x a 2 1y y b
AB ab
x
y
A 4,6
B 3,4
C 6, 6 D 6, 5
E 4, 2
O 0,0
4 0 4OA6 0 6
3 0 3OB4 0 4
6 0 6OC6 0 6
4 6 2DE
2 5 3
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1. PQ P Q (1) 3,2P 6,8Q (2) 4,3P 1,1Q
(1)
3
6
36
28PQ
(2)
3
4
41
)3(1PQ
2.
() 1 (1,3) (4,8) (4 1) i 8 3 j 3i 5 j
2 (3,5) (8,2) (8 3) i 2 5 j 5i 3 j 3 ( 4,2) (3,5) ( 3 4 ) i 5 2 j i 3 j 4 (0,0) (4, 3) (4 0) i 3 0 j 4i 3 j 5 (0,0) (4,4) (4 0) i 4 0 j 4i 4 j
3. 2,6A 3,8B D ABCD C
(1) 1,1C (2) 4,3C (3) 6,5C (4) 7,1C
D y,x
(1)
1y
1xCD
23
68AB
1y
1xCD
1
2AB
ABCD
1
2
1y
1x
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x 1 = 2 y + 1 = - 1 x = 3 y = - 2 D (3,-2)
(2)
4y
3xCD
1
2AB
ABCD
1
2
4y
3x
x + 3 = 2 y - 4 = - 1 x = -1 y = 3 D (-1,3)
(3)
6y
5xCD
1
2AB
ABCD
1
2
6y
5x
x 5 = 2 y - 6 = - 1 x = 7 y = 5 D (7,5)
(4)
7y
1xCD
1
2AB
ABCD
1
2
7y
1x
x + 1 = 2 y + 7 = - 1 x = 1 y = - 8 D (1,-8)
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4. 3,4A 5,1B C CD ABCD D
(1) 2,1D (2) 3,4D
(1)
8
5
35
41AB
y2
x1CD
ABCD
8
5
y2
x1
-1- x = -5 -2 - y = 8 x = 4 y = -10 C (4,-10)
(2)
8
5
35
41AB
y3
x4CD
ABCD
8
5
y3
x4
4 - x = -5 3 - y = 8 x = 9 y = -5 C (9,-5)
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5. A(3,2)
5
3AB B
A )y,x(11
B )y,x(22
5
3AB =
12
12
yy
xx =
2y
3x
2
2
2
x - 3 = - 3 2
x = 0
2y - 2 =5
2y =7
B (0,7)
6. B(-4,5) 2AB2
A
A )y,x(11
B )y,x(22
2
2AB =
12
12
yy
xx =
1
1
y 5
x4
- 4 - 1
x = 2 1
x = - 6 5 -
1y = - 2
1y = 7
A (-6,7)
3
x , y , z x
y
z
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x
y
z
(O) P(x, y,z) 1 1 1P(x , y ,z )
2 2 2Q(x , y ,z ) 2 1
2 1
2 1
x x
PQ y y
z z
Z
X
Y
O
P x, y, z
OP
1.
() 1 (1,3,7) (4,8,10) (4 1) i 8 3 j 10 7 k 3i 5 j 3k
2 (3,5,4) (8,2,9) (8 3) i 2 5 j 9 4 k 5i 3 j 5k 3 ( 4,2,1) (3,5, 10) ( 3 4 ) i 5 2 j 10 1 k i 3 j 9k 4 (0,0,0) (4, 3,5) (4 0) i 3 0 j 5 0 k 4i 3 j 5k 5 (0,0,0) (4,4,4) (4 0) i 4 0 j 4 0 k 4i 4 j 4k
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a c
b d
a c b d
a d
b e
c f
a d,b e c f
a c a cb d b d
a d a d
b e b e
c f c f
0
0
0
0
0
ab
a
b
ab
a
b
c
a
b
c
a
b
c
a c a cb d b d
a d a d
b e b e
c f c f
a a
b b
a a
b b
c c
2. 4u1
, 2v7
1. u v 2. u v 3. 3u 4. 2u 3v
1. 4 2 6u v1 7 6
2. 4 2 2u v1 7 8
3. 4 3(4) 123u 31 3( 1) 3
4. 4 72u 3v 2 31 2
= 8 212 6
= 294
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3. 4
u 1
2
3u
34 3(4) 12
u 3 1 3( 1) 3
2 3(2) 6
4.
1 3u
4
2v7
3 2
4 7
2 3u
4
6v8
3 6
4 8
3 2u
2 2
1
v2
2 1
2 2 2
4. 1u
4
2v8
1 2
4 8
5 1u
2
2v4
1 2
2 4
6 8u
4
4v2
8 4
4 2
7 1u 2
1
2
v 4
2
1 2 1
2 4 2
8. 1u 2
1
4
v 5
6
1 2 1
4 5 6
9. 1u 2
4
2
v 4
8
1 2 4
2 4 8
10. 2u 3
4
4
v 6
8
2 3 4
4 6 8
1. u v u kv k 2. u v
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(unit vector )
O
y
x
2 2Q x , y
1 1P x , ya
b
PQ
z
y
x
O
1 1 1P x , y , z
2 2 2Q x , y , z
PQ
1) ab
2 2a b
2) ab
2 2
a1
ba b
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3) a
b
c
2 2 2a b c
4) a
b
c
2 2 2
a1
ba b c
c
5) PQ PQ
1 i (
0
1
0
0
1
) , j (
1
0
0
1
0
) k (
1
0
0
)
1
u a i b j 2 2u a b
1 u 3i 4 j 5 2 u 6i 8 j 10 3 u 5i 12 j 13 4 u 15i 8 j 17 5 u 5i 12 j 13 6 u i 2 j 4k 21 7 u 2 i 2 j 2k 2 3 8 u 4i 2 j 6k 56 9 u 3i 4 j 5k 50 10 u i j k 3
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2. 1. u 6 i 8 j
2 2
u 6i 8 j 6i 8 j 6 i 8 j
u 10 10 106 8
2. u 3i 4 j
2 2
u 3i 4 j 3i 4 j 3i 4 j
u 5 5 53 4
3. u 5i 12 j
2 2
u 5i 12 j 5i 12 j 5i 12 j
u 13 13 135 12
4. u 7 i 24 j
2 2
u 24i 7 j 24 i 7 j 24 i 7 j
u 25 25 2524 7
5. 5 u 2 i 3 j
2 2
u 2i 3 j 2 i 3 j 2 i 3 j5 5 5 5
u 13 13 132 3
6.3 u 3i 4 j
2 2
u 3i 4 j 3i 4 j 3i 4 j3 3 3 3
u 5 5 53 4
7.10 u 8i 15 j
2 2
u 24i 7 j 24 i 7 j 24 i 7 j
u 25 25 2524 7
8. 7 u 7 i 24 j
2 2
u 24i 7 j 24 i 7 j 24 i 7 j7 7 7 7
u 25 25 2524 7
9. u 2i 6 j 3k
2 2 2
u 2i 6 j 3k 2i 6 j 3k 2i 6 j 3k
u 7 7 7 72 6 3
10. u i 2 j 4k
2 2 2
u i 2 j 4k i 2 j 4k i 2 j 4k
u 21 21 21 211 2 4
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11. u 2i 5 j 2k
2 2 2
u 2i 5 j 2k 2i 5 j 2k 2i 5 j 2k
u 33 33 33 332 5 2
12. 18 u i 4 j 8k
2 2 2
u i 4 j 8k i 4 j 8k18 18 18 2i 8 j 16k
u 91 4 8
(direction cosines ) a
1
2
3
a
a a
a
a 0 X , Y , Z
31 2 aa a, ,a a a
z
y
x
R
S
Q
O
1 2 3P a ,a ,a
2
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P(-1,2,3) Q(2,3,5)
PQ =
35
23
)1(2
=
8
1
3
PQ = 74)8(13 222
PQ 74
8,
74
1,
74
3
3.4 1 1u x i y j 2 2v x i y j u v 1 2 1 2u.v x x y y 1 1 1u x i y j z k 2 2 3v x i y j z k u v 1 2 1 2 1 2u.v x x y y z z u v u v 1. u 2 i 3 j 4 i j u v v u u v 2i 3 j . 4 i j = 2 4 3 1 = 38 = 5 v u 4i j . 2 i 3j = 4 2 1 3 = 38 = 5
2 4
u 1
2
2
v 3
4
u v
4 2
u v 1 . 3 4 2 1 3 2 4 13
2 4
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1. u, v w a 1) u v v u ( ) 2) u v w u v u w ( ) 3) a u v au v u av 4) 0 u 0 5) 2u u u 6) i i j j k k 1 i j i k j k 0 2. u v 0 180 u v u v cos () 3. u v u v u v 0
v
u
v
u
v
u
u
v 180u v
u
v
u
v
u v u v cos vu
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21 u.u u 2 u.v u v cos 2 2 23 u v u 2u v v 2 2 24 u v u 2u v v 2 2 2 25 u v u v 2 u 2 v 2 26 u v u v 4u v 2 27 u v . u v u v 2 2 2 28 u v w u v w 2u v 2v w 2w u 2 2 2 29 u v w u v w 2u v 2v w 2w u 2 2 2 210 u v w u v w 2u v 2v w 2w u 11 u v . w s u w u s v w v s 2 2 22 212 au bv a u 2abu v b v 3 1 3
u4
4v3
u v 0
2 3u
4
6v8
u v 0
3 2u
2
1v1
u v 0
4. 1u4
5v8
u v 0
5 1u2
2v1
u v 0
6 8u
4
4v2
u v 0
7 1u 2
1
2
v 4
2
u v 0
8. 1u 2
1
4
v 5
6
u v 0
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9. 1u 2
1
0
v 4
8
u v 0
10. 2u 3
4
4
v 6
8
u v 0
4 . u v u 5 , v 8 vu
vu u v 1. 0 2. 30 ( 1 ) 0 2 2 2u v u v 2 u v cos 2 22u v 5 8 2 5 8 cos0 2u v 25 64 2 5 8 1 2u v 169 u v 169 13
2 2 2u v u v 2 u v cos 2 22u v 5 8 2 5 8 cos0 2u v 25 64 2 5 8 1 2u v 9
u v 9 3 ( 2 ) 30 2 2 2u v u v 2 u v cos 2 22u v 5 8 2 5 8 cos30
2 3u v 25 64 2 5 82
2u v 89 40 3
u v 89 40 3 2 2 2u v u v 2 u v cos 2 22u v 5 8 2 5 8 cos30
2 3u v 25 64 2 5 82
2u v 89 40 3
u v 89 40 3
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5 u v 5 2 | u v | 26 u v 1. 3 2. 6 3. 8 4. 12 | u v | 5 2 | u v | 26
2 2 2 2 2 2| u v | | u v | (| u | | v | 2u v) (| u | | v | 2u v) 2 2(5 2) ( 26) 4u v
50 26 4u v 24 4u v
24u v 64
2.
6 u v 60 | u v | 37, | u v | 13 | u | | v | 1. 5 2. 7 3. 37 4. 50 2 2 2| u v | | u | 2u v | v | 37 ..(1)
2 2 2| u v | | u | 2u v | v | 13 ..(2) (1)+(2) 2 22 | u | 2 | v | 50 2 2| u | | v | 25 ..(3) (1)-(2) 4u v 24
u v 6 | u || v | cos60 6 (u v | u || v |)cos
1| u || v | 62
4 ; 2 | u || v | 24 (4) (3)+(4) 2 2| u | 2 | u | | v | | v | 49 2(| u | | v |) 49
| u | | v | 7 2. 7 u v u v
u.v u v cos
-1
u v 2 2 4cos
4 1 4 1 4 4u v
8 8cos cos
9 9
u 2 i j 2k , v i 2 j 2k
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8 u i 3 j, v 2i j (u v) (u v) cos
1. 5
1 2 . 5
2 3. 5
1 4. 5
2
u i 3 j, v 2i j
u v 3i 4 j, u v i 2 j 2 2| u v | 3 4 25 5 2 2| u v | ( 1) 2 5 (u v) (u v) 3( 1) 4(2) 3 8 5 (u v) (u v) | u v || u v | cos
5 5 5 cos 5 1cos
5 5 5 1.
9. u v u v u v u 2v u 2v 2u v | u | 2 cos
1. 10
1 2. 6
1 3. 4
1 4. 2
1
u v u 2v (u v) (u 2v) 0
2 2| u | u v 2 | v | 0 (1) u 2v 2u v (u 2v) (2u v) 0
2 22 | u | 3u v 2 | v | 0 (2) (2)-(1) 2| u | 4u v 0 2( 2) 4u v 0
1u v2
.(3)
(1) 5| v |2
(3) 10
1cos 1.
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10. u ai bj a 0 b 0 u (5i 2 j) 14 u
i 3cos5
a b
1. 7 2. 14 3. 18 4. 21 u (5i 2 j) (ai bj) (5i 2 j) 5a 5b 14
5a 14b2
u i | u || i | cos
2 2 29a (a b )25
3a b4
3 (5a 14) 426,4 2 23
56b 8,23
a b 6 8 14 2 11. u v 6 u v 2 u v
2 2u v u v 4u v
2 2
6 2 4u v
4 4u v u v 1 12 A,B,C O OA 3i 2 j
OB 2i 5 j 2AC AB3
2| OC |
1. 9
113 2. 9
98 3. 9
193 4. 9
159
AB OB OA (2i 5 j) (3i 2 j) i 7 j
2 2AC AC ( i 7 j)3 3
OC OA AC
2 7 8(3i 2 j) ( i 7 j) i j3 3 3
2 49 64 113| OC |9 9 9
1.
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13. u 4i 3 j,| v | | u | | u v | 8 u.v 1. 6 2. 7 3. 12 4. 14
u 4i 3 j 2 2| v | | u | 4 3 5 2 2 2u v u 2u v v 2 2 28 5 2u v 5
64 25 25u v 72
2.
14. u,v,w u 5v 2w 0 u 3i 4 j u v u w | w | cos 1. 2 2. 2.5 3. 3 4. 3.5
u 3i 4 j 2 2| u | 3 4 5 u v u v 0 u 5v 2w 0 ..(1)
u 5v 2w 2 2| u 5v | | 2w | 2 225 | v | 4 | w | 25 (2) (1) 5v 2w u 2 2 225 | v | 4 | w | 4w u | u | ....(3)
(2)=(3) 50| w | cos 2.520
2.
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2 3 1u , v , w3 0 4
1. 2 3 5u v3 0 3
2. 2 1 2 2 0u 2w 23 4 3 8 5
3 . u v 2 3 3 0 6
4. 1 1 6
u v w 2 3 3 0 64 4 24
5. u v w
6. 22u 2 3 13
7 . 2 2v 3 0 3
8. Cos u v u v u v cos
u v 6 2cos3 13 13u v
9 . 2 3 1 2 4
u v w . 8 12 203 0 4 3 4
10. 2 1 2 3u v u w . 2 12 6 0 203 4 3 0
11. 1 u
2
3u 2 i 3 j
13 13 13u
12. 3 v
3
0v3 3 3i
3v
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(Projection Vectors)
y
x
v
u
O
A
OA (Projection Vectors) v u
2
u.vOA u
u
1. O , OA 3i 4 j,OB 5i 2 j A OB D OD
1. 7 5i 2 j29
2. 7 5 i 2 j29
3. 8 5i 2 j29
4. 8 5 i 2 j29
A
B
D
O
OA 3i 4 j, OB 5i 2 j 22OB 5 2 29
OB.OA 5 3 2 4 7
2
OB.OAOD OB
OB
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2
7OD 5i 2 j
29
7OD 5i 2 j29
2. OA 3i 4 j, OB 12 i 5 j BC OA C OC
1. 5 3i 4 j16
2. 16 3i 4 j5
3. 16 3i 4 j25
4. 25 3i 4 j16
A
B
C
O
OB 12i 5 j OA 3i 4 j 22OA 3 4 5
OB.OA 12 3 5 4 16
2
OB.OAOC OA
OA
2
16OC 3i 4 j
5
16OC 3i 4 j25
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3 . OA 3i 4 j, OB 12 i j AC OB C OC
1. 8 12 i j29
2. 29 12 i j8
3. 40 12 i j145
4. 140 12 i j45
y
x
A
O
C
B
OA 3i 4 j
OB 12 i j 2 2OB 12 1 145 OB.OA 12 3 1 4 40
2
OB.OAOC OB
OB
240
OC 12i j
145
OC 40 12 i j145
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C AB
O
m n
vu
w
nu mvwm n
2 2B x , y 1 1A x , y
m n
C x, y
2 1mx nxx
m n
2 1my nyym n
1. ABC D AB AB AD : DB 3: 2 CA 3i 2 j, CB 2 i 3 j CD
1. 95
2. 115
3. 135
4. 145
C
AB
D
3 2
CA 3i 2 j CB 2 i 3 j
3CB 2CACD
5
3 2 i 3 j 2 3i 2 j
5
6i 9 j 6 i 4 j
5
12
i j5
2
212 13CD 15 5
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2. A,B,C O OA 3i 2 j
OB 2 i 5 j 2AC AB3
2
OC
1. 1139
2. 989
3. 1939
4. 1539
CAB
O
2 1
OA 3i 2 j OB 2 i 5 j
2OB 1OAOC
2 1
2 2 i 5 j 1 3i 2 j
2 1
2 12 i 5 j 3i 2 j
3 3
7 8
i j3 3
2 2
2 7 8 113OC
3 3 9
3. A 3, 2 ,B 9,4 O 0,0 AB 3 C D OC OD
C
O 0,0
3OA
2
9OB
4
D A 3, 2 B 9,41 1 1
3OA
2
9OB4
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3 9 52OA 1OB 2 1OC
2 4 02 1 3 3
3 9 71OA 2OB 1 2OD
2 4 22 1 3 3
OC OD 5 7 0 2 35
4 . A 1,1 ,B 4,10 ,C 7,9 D AB AD 2
3AB
CA DC cos
1. 25
2. 210
3. 25
4. 210
D
2 1
A 1,1
C 7,9
B 4,10
6CA
8
3CB
1
6CA
8
3CB1
1CA 2CBCD3
6 31 2
48 1CD
23
4DC
2
CA DC cos
6CA8
2 2
CA 6 8 10
4DC
2
2 2DC 4 2 20
CA.DC 6 4 8 2 40
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CA.DC CA . DC cos
CA.DC CA . DC cos
40 10 20 cos 2
cos5
5 . A B 10,0 2,4
AB C AC 1
3CB
O COB
1. 210
2. 110
3. 110
4. 210
C AB
O
3 1
OA 10 i OB 2 i 4 j
1OB 3OAOC
4
1 2 i 4 j 3 10 i
4
7 i j
7 2 1 4OC OB 1
cos50 20 10OC OB
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6. ABC D BC BD : BC 1:3
. 3AD 2AB BC . 21
AD BC BC6
1. . . 2. . . 3. . . 4. . .
A
BC2 1
D . 2AB 1ACAD
3
3AD 2AB 1AC .
. . 2 1AD BC AB AC BC3 3
2 1AB BC AC BC3 3
A
B
DC
2 1
120
60
aa
2 1AD BC AB BC AC BC
3 3
2 1AD BC AB BC cos AC BC cos3 3
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a
22 1 1AD BC a a cos120 a a cos 60 a3 3 6
. 3. 7 . A,B, C D BC
BD : DC 2 :1 2 2 2
AD a AB b AC c AB AC a,b,c
AB AC 0 2 2 2a b c
1. 3181
2. 3281
3. 1027
4. 1127
A
B C2 1
D 1AB 2ACAD
3
1 2AD AB AC3 3
1 2
AD AB AC3 3
2 2 21 4 4
AD AB AB AC AC9 9 9
2 2 2
2 2 2 1 4 4 11a b c9 9 9 27
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3.5
1
2
3
a
u a
a
1
2
3
b
v b
b
2 3 3 2
3 1 1 3
1 2 2 1
a b a b
a b a b
a b a b
2 3 1 3 1 22 3 1 3 1 2
a a a a a ai j k
b b b b b b
u v
1 2 31 2 3
i j k
u v a a a
b b b
1. u,v,w k 1) u v v u 2) u v w u w v w 3) u v w u v u w 4) u kv k u v 5) ku v k u v 6) u u 0 7) i j k , j k i , k i j 2. u,v,w u v w u v w 3. u 0 v 0 u v u v sin u v 0 180 4. u v u v u v
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1. 4
u 2
4
6
v 3
0
u v
u v = i j k
4 2 4
6 3 0
= 2 4 4 4 4 2i j k3 0 6 0 6 3
= ( 2 0 3 4 ) i ( 4 0 4 6 ) j ( 4 3 2 6 k = 12 i 24 j 0k = 12 i 24 j
v
u
v sin
v
u
v sin
u v u v sin 1 1u v u v sin2 2
v r
u
h r
v u , v r h u v r u v r h u cos v r
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= v r u cos = u v r cos u v r
u , v w )wv(u = 0
1 2 3 1 2
1 2 3 1 2
1 2 3 1 2
u u u u u
(u v) r v v v v v
w w w w w
1. ABCD AB 2 i j k AD i j 2k AB AD
i j k
AB AD 2 1 1
1 1 2
1 1 2 1 2 1i j k1 2 1 2 1 1
= 1 2 1 1 i 2 2 1 1 j 2 1 1 1 k = i 3 j k 2 2 2AB AD 1 3 1 11
2. u i 2 j 3k , v 2 i 3 j , r j 2k u v r
i j k
v r 2 3 0
0 1 2
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= 3 0 2 0 2 3i j k1 2 0 2 0 1
= 6 i 4 j 2k u v r i 2 j 3k 6 i 4 j 2k
= 1 6 2 4 3 2 = 686 = 20 = 20 3 u i 2 j , v 3i j 5k , r 2 i 7k
1 2 0 1 2
u v r 3 1 5 3 1
2 0 7 2 0
7 20 0 0 0 42 55 5555
4. 3 A, B C A i 2j k , B 21 3k C 7j 4k
1 2 1 1 2
(A B) C 2 0 3 2 0
0 7 4 0 7
(A B) C -23 23