№1 Given four points A1 (4; 2; 5); A2 (0; 7; 1); A3 (0; 2; 7); A4 (1; 5; 0). Draw up the equations: a) plane A1A2A3; b) straight line A1A2; c) direct A4M; perpendicular to the plane A1A2A3; d) direct A3N; parallel line A1A2; e) a plane passing through point A4; perpendicular to the straight line A1A2. Calculate: e) the sine of the angle between the straight line A1A4 and the plane A1A2A3; g) the cosine of the angle between the Ohu coordinate plane and the A1A2A3 plane.

№2 Make an equation for the plane passing through the point A (2; 3; –4) parallel to two vectors a = {4; 1; -1 }; c = {2; -1; 2}.

№3 Under what conditions m and C is the line perpendicular to the 3x - 2 y + Cz + 1 = 0 plane.