Take A is origin. Let be position vectors of B, C respectively so that
L.H.S. =
= (P.V. Of E - P.V. of B) + (P.V. of C - P.V. of D)
If are distinct non-zero vectors represented by directed lines from the origin to the points A, B, C and D respectively and if
, then prove that ABCD is a parallelogram.
If A and B are two points in space and if they become respectively A', B' on a translation, show that