Let the point P(−9,12,−15) divides the line joining A=(1,−2,3) and B=(−4,5,−6) in ratio λ : 1 then, −9=
−4λ+1
λ+1
,λ=−2 So, the harmonic conjugate of point P with respect to the line segment AB will divide the line segment AB internally in ratio 2:1, so, point will be, (