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QJEEM24Mab859: JEE Main 2024 Mathematics - Class 12 JEEM24Mab859 Solution: Consider the system of linear equations , where . Then, which…

Consider the system of linear equations x+y+z=5,x+2y+λ2z=9,x+3y+λz=μx+y+z=5, x+2 y+\lambda^2 z=9, x+3 y+\lambda z=\mu , where λ,μ∈R\lambda, \mu \in \mathbb{R} . Then, which of the following statement is NOT correct?

Multiple Choice Options

  • A System is consistent if λ≠1\lambda \neq 1 and μ=13\mu=13
  • B System is inconsistent if λ=1\lambda=1 and μ≠13\mu \neq 13
  • C System has unique solution if λ≠1\lambda \neq 1 and μ≠13\mu \neq 13
  • D System has infinite number of solutions if λ=1\lambda=1 and μ=13\mu=13

Step-by-Step Verified Solution

amp;∣1amp;1amp;11amp;2amp;λ21amp;3amp;λ∣=0amp;⇒2λ2−λ−1=0amp;λ=1,−12amp;∣1amp;1amp;52amp;λ2amp;93amp;λamp;μ∣=0⇒μ=13\begin{aligned}& \left|\begin{array}{ccc}1 & 1 & 1 \\1 & 2 & \lambda^2 \\1 & 3 & \lambda\end{array}\right|=0 \\& \Rightarrow 2 \lambda^2-\lambda-1=0 \\& \lambda=1,-\frac{1}{2} \\& \left|\begin{array}{ccc}1 & 1 & 5 \\2 & \lambda^2 & 9 \\3 & \lambda & \mu\end{array}\right|=0 \Rightarrow \mu=13\end{aligned}

Infinite solution λ=1&μ=13\lambda=1 \& \mu=13

For unique sol⁡nλ≠1\operatorname{sol}^{\mathrm{n}} \lambda \neq 1

For no sol⁡nλ=1&μ≠13\operatorname{sol}^{\mathrm{n}} \lambda=1 \& \mu \neq 13

If λ≠1\lambda \neq 1 and μ≠13\mu \neq 13

Considering the case when λ=−12\lambda=-\frac{1}{2} and μ≠13\mu \neq 13 this will generate no solution case

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