Find the position vector of a point R which divides the line joining two points P and Q whose position vectors are respectively, in the ratio 2 : 1

(i) internally (ii) externally

Given that and

(i) The lies on the segment PQ(internal division).If m:n is the ratio in which divides PQ, then

Given m:n=2:1, m=2 and n=1

(ii) The does not lie on the segment PQ(external division).If m:n is the ratio in which divides PQ,then

Given m:n=2:1, m=2 and n=1

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