№1 Given four points A1 (1; 8; 2); A2 (5; 2; 6); A3 (5; 7; 4); A4 (4; 10; 9). 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) the 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 Find the values ​​of the segments cut off on the coordinate axes by a plane passing through the point M (2; –3; 3) parallel to the plane 3x + y – 3z = 0.

№3 At what values ​​of A and B is the plane Ax + By + 6z - 7 = 0 perpendicular to the line ...?