|=0 On expansion of determinant along R , we get x[(−3x)(x+2)−2x(x−3)]+6[2(x+2)+3(x−3)] −1[9(2x)−(−3x)(−3)]=0 ⇒x[−3x2−6x−2x2+6x]+6[2x+4+3x−9]−1[4x−9x]=0 ⇒x(−5x2)+6(5x−5)−1(−5x)=0 ⇒−5x3+30x−30+5x=0 ⇒5x3−35x+30=0⇒x3−7x+6=0. Since all roots are real ∴ Sum of roots =−