NDA2011MathematicsDeterminantsActual
. If the matrix A= ( array ccc 2-x & 1 & 1 1 & 3-x & 0 -1 & -3 & -x array ) is singular, then what is the solution set S ?
Options
- AS= 0,2,3
- BS= -1,2,3
- CS= 1,2,3
- DS= 2,3
Correct answer
A. S= 0,2,3
Step-by-step solution
Since the matrix is singular therefore, | array ccc 2-x & 1 & 1 1 & 3-x & 0 -1 & -3 & -x array |=0 aligned & R ₂ ( R ₃+ R ₂ ) & | array ccc 2-x & 1 & 1 1 & 3-x & 0 0 & -x & -x array |=0 aligned aligned & . (2-x) -3 x+x^2 ) -1(-x+x)=0 & (2-x) (x^2-3 x )=0 & x(2-x),(x-3)=0 & x=0, x=2, x=3 aligned