P (-1,4), Q(11,-8) divides AB harmonically in the ratio 3:2 then A,B are

A, B divides PQ harmonically in the ratio m-n:m+n

A, B  divides PQ in the ratio 1:5 internally and externally

A=$$\begin{gathered} \left(\frac{11-5}{1+5},\frac{-8+20}{1+5}\right)=\left(1, 2\right) \\ \left(\frac{11+5}{1-5},\frac{-8-20}{1-5}\right)=\left(-4,7\right) \end{gathered}$$