Since 2−√3 is a root, we know that 2+√3 is also a root, and corresponding to this pair of roots we have the quadratic factor x2−4x+1.
Also 6x4−13x3−35x2−x+3=(x2−4x+1)(6x2+11x+3);
Hence the other roots are obtained from
6x2+11x+3=0, or (3x+1)(2x+3)=0;
Thus, the roots are −13,−32,2+√3,2−√3.