JEE Advanced 2014Paper 1
- Exam
- JEE Advanced
- Year
- 2014
- Paper
- Paper 1
- Subject
- Mathematics
- Chapter
- Matrices
JEE Advanced 2014 · Paper 1 · Mathematics · Matrices
Let M be a 2 × 2 symmetric matrix with integer entries. Then M is...
Let M be a symmetric matrix with integer entries. Then M is invertible if
Options
- AThe first column of M is the transpose of the second row of M
- BThe second row of M is the transpose of the first column of M
- CM is a diagonal matrix with non - zero entries in the main diagonal
- DThe product of entries in the main diagonal of M is not the square of an integer
Correct answer
C. M is a diagonal matrix with non - zero entries in the main diagonal
Step-by-step solution
Let \left[\right]\in IM = ab - {c}^{2}a = b = c, Det\left(M\right) = 0c = 0, a, b \ne 0, Det\left(M\right) \ne 0ab \neDet\left(M\right) \ne 0