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QJEEM20Mab5a3: JEE Main 2020 Mathematics - Class 12 JEEM20Mab5a3 Solution: The values of and for which the system of linear equations x +…

The values of λ\lambda and μ\mu for which the system of linear equations
x + y + z = 2
x + 2y + 3z = 5
x + 3y + λ\lambda z = μ\mu
has infinitely many solutions are, respectively:

Multiple Choice Options

  • A 6 and 8
  • B 5 and 8
  • C 5 and 7
  • D 4 and 9

Step-by-Step Verified Solution

For infinite many solutions

D = D1 = D2 = D3 = 0

Now D = |11112313λ| = 0

⇒\Rightarrow 1. (2 λ\lambda – 9) –1.( λ\lambda – 3) + 1.(3 – 2) = 0

⇒\Rightarrow λ\lambda = 5

Now D1 = |211523μ35| = 0

⇒\Rightarrow 2(10 – 9) –1(25 – 3 μ\mu ) + 1(15 – 2 μ\mu ) = 0

⇒\Rightarrow μ\mu = 8

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