E Maths - Vectors In 2 Dimensions

• anpanman

  6 Mar 09, 16:38

  In the diagram, ABCDEF is a regular hexagon, a, b, and c are the position vectors of A , B and C with respect to the point O respectively. Express the following vectors in terms of a,b and c.    (a) AD->                  Have been trying this question for a day in vain. I can't get the answer. It is 2c - 2b

• Darkness_hacker99

  6 Mar 09, 18:11

  Regular Hexagon.

  Property:
  The longest diagonal length of the haxagon = length of side x 2.
  *Remember*

  So the answer is 2BC.

  2BC = 2 (-b + c)

  = 2(c-b)

  = 2c - 2b.