JEE Main 2024 Mathematics question
The values of m, n, for which the system of equations x + y + z = 4, 2x + 5y + 5z = 17, x + 2y + mz = n has infinitely many solutions, satisfy the equation:
Answer: (D)
Solution
The coefficient determinant vanishes for m = 2, and the consistency condition then gives n = 7, so m² + n² − mn = 4 + 49 − 14 = 39.