The position vector of the point which divides the join of points and in the ratio 3 : 1 is


We are given points and .


Let these points be


and .


Also, given in the question that,


A point divides AB in the ratio of 3 : 1.


Let this point be C.


C divides AB in the ratio = 3 : 1


We need to find the position vector of C.


We know the position vector of a point C dividing the line segment joining the points P and Q, whose position vectors are p and q in the ratio m : n internally is given by,



According to the question, here


m : n = 3 : 1


m = 3 and n = 1


Also,


And


Substituting these values in the formula above, we get






Thus, position vector of the point is .

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