JEE Main 20208 JanuaryEvening Shift
- Exam
- JEE Main
- Year
- 2020
- Date
- 8 January
- Shift
- Evening Shift
- Subject
- Mathematics
- Chapter
- Determinants
JEE Main 2020 · 8 January · Evening Shift · Mathematics · Determinants
The system of linear equations + 2y + 2z = 5 2 + 3y + 5z = 8 4x + +...
The system of linear equations
has
has
Options
- Ano solution when
- Ba unique solution when
- Cno solution when
- Dinfinitely many solutions when
Correct answer
C. no solution when
Step-by-step solution
∆ = \left|\begin{cases}\lambda & 2 & 2 \\ 2\lambda & 3 & 5 \\ 4 & \lambda & 6\end{cases}\right| = \lambda\left(18 - 5\lambda\right) - 2\left(12\lambda - 20\right) + 2\left(2{\lambda}^{2} - 12\right) = - {\lambda}^{2} - 6\lambda + 16 = \left(\lambda + 8\right)\left(2 - \lambda\right)
for ,
{∆}_{1} = \left|\begin{cases}5 & 2 & 2 \\ 8 & 3 & 5 \\ 10 & 2 & 6\end{cases}\right|
No solution for .