2.1.
a, b, c, | |
| a |, || | |
ax, ay, az | |
r 1 = (x 1, y 1, z 1), r 2 = (x 2, y 2, z 2) | - (x 1, y 1, z 1), (x 2, y 2, z 2) |
a b, ab | |
a 2 | |
b a | a b |
a ´ b | |
^ | |
|| | |
Ð | |
abc, (abc) |
2.2.
, | ||
a = ax i + ay j + az k = (ax, ay, az) | ||
; cos2a + cos2b + cos2g = 1 | ||
a + b = (ax + bx, ay + by, az + bz) | ||
l a = (l ax, l ay, l az) | ||
A (x 1, y 1, z 1) B (x 2, y 2, z 2) | = (x 2- x 1) i + (y 2- y 1) j + (z 2- z 1) k | |
AB, A (x 1, y 1, z 1) B (x 2, y 2, z 2) | l = | r 2- r 1 |; l = | |
a b (a || b) | l a = b | |
a b | b a = | a | cos j, j =Ð(a, b) | |
AB l = AC / CB, A (x 1, y 1, z 1), B (x 2, y 2, z 2), (x, y, z) : | ||
, a b | d 1,2 = | a b |; d 1,2 = | |
2.3.
, | |||||
ab = | a |×| b | cosj, j =Ð(a, b) | |||||
× | i | j | k | ||
i | |||||
j | |||||
k | |||||
ab = axbx + ayby+ azbz | |||||
a 2 = | a |2 = | |||||
: 1) 2) 3) | ab = ba l(ab) = (l a) b = a (l b) a (b + c) = ab + ac | ||||
ab = 0 a ^ b | |||||
axbx + ayby+ azbz = 0 | |||||
: 1) 2) a b | cosj = = b a = |
|
|
2.4.
, | |||||
a ´ b = c, | c | = | a |×| b | sin j, j =Ð(a, b), c ^ a, c ^ b (a, b, c) - | |||||
´ | i | j | k | ||
i | o | k | - j | ||
j | - k | o | i | ||
k | j | - i | o | ||
: 1) 2) 3) | a ´ b = - b ´ a l(a ´ b) = (l a)´ b = a ´(l b) a ´(b + c) = a ´ b + a ´ c | ||||
a||b | |||||
: 1) , a b 2) , a b | | a ´ b | = | a ´ b | = |
:
- i, j, k
2.5.
, | |
(a ´ b)× c = abc | |
: 1) 2) 3) a, b, c ) , ) , | abc = - acb = - cba = - bac abc = bca = cab abc > 0 abc < 0 |
abc =0 a, b, c - | |
: 1) , a, b, c 2) , a, b, c 3) , a, b, c | | abc | | abc | | abc | |