NDA2024MathematicsDeterminantsActual
For what value of n is determinant | array ccc C (9,4) & C (9,3) & C (10, n-2) C (11,6) & C (11,5) & C (12, n) C (m, 7) & C (m, 6) & C (m+1, n+1) array |=0 for every m n ?
Options
- A4
- B5
- C6
- D7
Correct answer
C. 6
Step-by-step solution
| array ccc C (9,4) & C (9,3) & C (10, n-2) C (11,6) & C (11,5) & C (12, n) C (m, 7) & C (m, 6) & C (m+1,7)- C (m+1, n+1) array |=0 aligned & Applying C ₃ C ₁+ C ₂- C ₃ & | array lcc C (9,4) & C (9,3) & C (10,4)- C (10, n-2) C (11,6) & C (11,5) & C (12,6)- C (12, n) C (m, 7) & C (m, 6) & C (m+1,7)- C (m+1, n+1) array |=0 & Value of determinant =0 & C ₃=0 n-2=4 n=6 . aligned