$ \Rightarrow {\rm{k}}({\rm{k}} + 2)({\rm{k}} - 1) \ne 0 \Rightarrow {\rm{k}} \ne - 2,0,1$ so ${\rm{k}} = - 1$
$ 11 x+y+\lambda z=-5 $
$ 2 x+3 y+5 z=3 $
$ 8 x-19 y-39 z=\mu$
ને અસંખ્ય ઉકેલો હોય, તો $\lambda^4-\mu=$.............