We have, x4−2x3+x−380=0 ⇒ x4−2x3+x2−x2+x−380=0 (x2−x)2−(x2−x)−360=0 Let x2−x=y y2−y−360=0 ⇒ y2+19y−20y−360=0 y(y+19)−20(y+19)=0 (y−20)(y+19)=0 ⇒ (x2−x−20)(x2−x+19)=0 ⇒ (x−5)(x+4)(x2x+19)=0 Complex roots are obtained from the equation x2−x+19=0 Sum of the complex roots of the equation