1. Show a^2 b^2 = a.b a.b + a ^ b . a ^ b
2. A plane with position vectors a, b and c, find the distance of a fourth, with position vector r, from the plane.
3. A plane with the point (1, -2, 1) and the line r = (1+3?)i + (?-1)j - 2?k. Find the distance of the plane from the origin.
If someone could start me off in the right direction that would be great.