Find the position vector of a point R which divides the line joining A(-2, 1, 3) and B(3, 5, -2) in the ratio 2 : 1 (i) internally (ii) externally.
A = (-2,1,3)
B = (3,5,-2)
Formula to be used – The point dividing a line joining points a and b in a ratio m:n internally or externally is given by 
respectively.
The position vector of the point dividing the line internally
The position vector of the point dividing the line externally
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