Find the position vector of a point which divides the join of points with position vectors and externally in the ratio 2 : 1.
If A is a square matrix such that A² = A, then write the value of 7A – (I + A)³, where I is an identity matrix.
State the reason for the relation R in the set {1, 2, 3} given by R = {(1, 2), (2, 1)} not to be transitive.