Option 8 DHS 2.2

DHS - 2.2
№ 1.8. Given the vector. It is necessary: ​​a) to calculate the mixed product of the three vectors; b) find the module of the vector product; c) calculate the scalar product of two vectors; d) check whether the two vectors are collinear or orthogonal; e) check whether the three vectors will be coplanar. a (4; 2; -3); b (2; 0; 1); c (-12; -6; 9)
№2.8. The vertices of the pyramid are at points A (7; 5; 8); B (–4; –5; 3); C (2; –3; 5); D (5; 1; –4). ...........
# 3.8. The force F (–9; 5; 7) is applied to the point A (1; 6; –3). Calculate a) the work force in the case; when the point of its application; moving straight moves to point B (4; –3; 5); b) the modulus of the moment of force relative to point B.