NDA2018MathematicsDeterminantsActual
What is the determinant of the matrix ( array ccc x & y & y+z z & z & z+x y & z & x+y array ) ?
Options
- A(x-y)(y-z)(z-x)
- B( x - z )( z - x )
- C( y - z )( z - x )
- D(z-x)^2(x+y+z)
Correct answer
D. (z-x)^2(x+y+z)
Step-by-step solution
| array lll x & y & y+z z & x & z+x y & z & x+y array |= R ₁ R ₁+ R ₂+ R ₃ | array ccc x+y+z & x+y+z & 2(x+y+z) z & x & z+x y & z & x+y array | aligned & =(x+y+z) | array ccc 1 & 1 & 2 z & x & z+x y & z & x+y array | & =(x+y+z)(z+x)^2,( replacing z by x) aligned