Option 9 DHS 2.2

DHS - 2.2
№1.9. Given the vector. It is necessary: ​​a) to calculate the mixed product of three three vectors; b) find the module of the vector product; c) calculate the scalar product of two vectors; d) check whether two are collinear or orthogonal
vectors; e) check whether the three vectors will be coplanar. a (-1; 0; 5); b (-3; 2; 2); c (-2; -4; 1).
№2.9. The vertices of the pyramid are at points A (3; –2; 6); B (–6; –2; 3); C (1; 1; –4); D (4; 6; –7). .......
No. 3.9. The force F (6; 5; –7) is applied to the point A (7; –6; 4). Calculate a) the work force in the case; when the point of its application; moving straight; moves to point B (4; 9; –6); b) the modulus of the moment of force relative to point B.