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Which statement about unique, infinite or no solutions of a system with parameters is (not) correct

This type of question, asked 9 times: 2021 Paper 2, 2021 Paper 26, 25 Jan 2023, 29 Jan 2023, 31 Jan 2023, 6 Apr 2023, 10 Apr 2023, 13 Apr 2023, 30 Jan 2024. All 10 questions below, oldest first.

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  1. Question 1

    2021 Paper 2

    72
    For the system of linear equations:
    x−2y=1,x−y+kz=−2,ky+4z=6,k∈Rx- 2y= 1,x-y+kz= - 2,ky+ 4z= 6,k\in R
    consider the following statements: (A) The system has unique solution if k≠2,k≠−2k\neq 2,k\neq - 2. (B) The system has unique solution if k=−2k= - 2. (C) The system has unique solution if k=2k= 2. (D) The system has no-solution if k=2k= 2. (E) The system has infinite number of solutions if k≠−2k\neq - 2. Which of the following statements are correct?

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  2. Question 2

    2021 Paper 26

    70
    Consider the following system of equations:
    x+2y−3z=ax + 2y - 3z = a
    2x+6y−11z=b2x + 6y - 11z = b
    x−2y+7z=cx - 2y + 7z = c
    Where a,ba,b and cc are real constants. Then the system of equations:

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  3. Question 3

    25 Jan 2023

    67
    Let S1S_{1} and S2S_{2} be respectively the sets of all a∈R−{0}\mathbf{a \in R - \{ 0\}} for which the system of linear equations
    ax+2ay−3az=1 (2a+1)x+(2a+3)y+(a+1)z=2 (3a+5)x+(a+5)y+(a+2)z=3\begin{matrix} & ax + 2ay - 3az = 1 \\ & \ (2a + 1)x + (2a + 3)y + (a + 1)z = 2 \\ & \ (3a + 5)x + (a + 5)y + (a + 2)z = 3 \end{matrix}
    has unique solution and infinitely many solutions respectively. Then

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  4. Question 4

    29 Jan 2023

    64
    Consider the following system of equations
    αx+2y+z=1\alpha x + 2y + z = 1
    2αx+3y+z=12\alpha x + 3y + z = 1
    3x+αy+2z=β3x + \alpha y + 2z = \beta
    for some α,β∈R\alpha,\beta \in R. Then which of the following is NOT correct.

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  5. Question 5

    31 Jan 2023

    72
    For the system of linear equations
    x+y+z=6x + y + z = 6
    αx+βy+7z=3\alpha x + \beta y + 7z = 3
    x+2y+3z=14x + 2y + 3z = 14
    which of the following is NOT true?

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  6. Question 6

    6 Apr 2023

    158
    For the system of equations
    x+y+z=6x + y + z = 6
    x+2y+αz=10x + 2y + \alpha z = 10
    x+3y+5z=βx + 3y + 5z = \beta, which one of the following is NOT true?

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  7. Question 7

    10 Apr 2023

    71
    For the system of linear equations
    2x−y+3z=52x - y + 3z = 5
    3x+2y−z=73x + 2y - z = 7
    4x+5y+αz=β4x + 5y + \alpha z = \beta
    Which of the following is NOT correct?

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  8. Question 8

    13 Apr 2023

    67
    For the system of linear equations
    2x+4y+2az=b2x + 4y + 2az = b
    x+2y+3z=4x + 2y + 3z = 4
    2x−5y+2z=82x - 5y + 2z = 8
    which of the following is NOT correct?

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  9. Question 9

    30 Jan 2024

    73
    Consider the system of linear equations x+y+z=4μ, x+2y+2λz=10μ, x+3y+4λ2z=μ2+15x+y+z=4\mu,\ x+2y+2\lambda z=10\mu,\ x+3y+4\lambda^{2}z=\mu^{2}+15, where λ,μ∈R\lambda,\mu\in R. Which one of the following statements is NOT correct?

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  10. Question 10

    30 Jan 2024

    151
    Consider the system of linear equations x+y+z=5,x+2y+λ2z=9x + y + z = 5,x + 2y +\lambda^{2}z = 9, x+3y+λz=μx + 3y + \lambda z = \mu, where λ,μ∈R\lambda,\mu \in R. Then, which of the following statement is NOT correct?

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