№1 Given four points A1 (3; 5; 4); A2 (8; 7; 4); A3 (5; 10; 4); A4 (4; 7; 8). Draw up the equations: a) plane A1A2A3; b) straight line A1A2; c) direct A4M; perpendicular to the plane A1A2A3; d) line A3N parallel to line A1A2; e) a plane passing through point A4; perpendicular to the straight line A1 A2. 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 points A (3; –1; 2); B (2; 1; 4) parallel to the vector a = (5; –2; –1).

№3 Make an equation of a line passing through point M (2; –5; 3); parallel to the line 2x - y + 3z - 1 = 0; 5x + 4y - z - 7 = 0.