defence exam Coast Guard Navik GD (General Duty) 02/2025 Mock Test Series Mathematics Determinants Evaluation of Determinants
If - 9 is a root of the equation \(\left| {\begin{array}{*{20}{c}} x&2&7\\ 2&x&2\\ 7&7&x \end{array}} \right|\) = 0, then the other two roots are
1
2, 7
2
-2, 7
3
2, -7
4
-2, -7