2.1 (1; 2; 3), (-1; 0; 3), (2; 1; -1) (3; 2; 2) . , , .
. , , , , :
.
.
, .
.
D1 =
;
D2 =
D3 =
, , , : = { -1/4, 7/4, 5/2}.
2.2 (5 + 3 )(2 - ),
.
10 × - 5 × + 6 × - 3 × = 10 ,
.. .
2.3 ,
.
.
= (1, 2, 3), = (6, 4, -2)
× = 6 + 8 6 = 8:
.
cosj =
2.4
.
.
= (2, 5, 1); = (1, 2, -3)
.
2.5 (2, 2, 2), (4, 0, 3), (0, 1, 0).
.
2.6 , ,
.
(2).
2.7 , (5; 7; 2), B(3; 1; -1), C(9; 4; -4), D(1; 5; 0) .
.
:
:
,
, , A, B, C D .
2.8 , BCD, A(0;0;1), B(2;3;5), C(6;2;3), D(3;7;2).
.
:
BCD.
S = (2)
.. V = ; ()
2.9. R3 -- , , ,
.
, --
- . ,
.
.
, : ,
,
, , , .