JEE Main 2017 (Offline)Question 1
If $S$ is the set of distinct values of $b$ for which the following system of linear equations
$x+y+z=1$
$x+ay+z=1$
$ax+by+z=0$
has no solution, then $S$ is :
Determinant
Solution
Subtracting first two equations: $(a-1)y=0$. If $a\ne1$ the system has a unique solution. If $a=1$ the equations are $x+y+z=1$ and $x+by+z=0$, inconsistent only for $b=1$. So $S=\{1\}$.