The position vectors of two points A and B are and respectively. Find the position vector of a point C which divides AB externally in the ratio 1 : 2. Also, show that A is the mid-point of the line segment CB.




Formula to be used – The point dividing a line joining points a and b in a ratio m:n externally is given by respectively.


The position vector of the point C dividing the line externally




The midpoint of B and C may be given by



i.e. point A


A is the midpoint of B and C.


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