Question
For no soin,
( begin{array}{rl}a & -1 & -1 1 & -a & 1 1 & -1 & -aend{array} mid=0 )
( left.a^{3}+a^{2}+1right)+1(-a-1)+1(a-1)=0 )
[
begin{array}{l}a^{3}-a=0-a+1=0 aleft(a^{2}-1right)=6 Rightarrow a=0 ;+1,-1end{array}
]

9. The - odru 36 (c) = 8 and u = 36 (d) None of these The system of equations ax - y -z = a -1, x - ay - Z = a -1, x - y - az = a -1 has no solution, if a is (a) either -2 or 1 (b)-2 (c) 1 (d) not (-2)
Solution
