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Consider a 2 x 2 matrix A, whose characteristic equation is given by 2A2 - 5 A + 2I = 0 . Then, the value of 2(Tr A)-3(det A) = ___________
    Correct answer is '2'. Can you explain this answer?
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    Consider a 2 x 2 matrix A, whose characteristic equation is given by 2...
    The characteristic equation o f A is
    According to Cayley - Hamilton theorem, eigenvalues of the matrix will also satisfy the characteristic equation i.e.  
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    Consider a 2 x 2 matrix A, whose characteristic equation is given by 2...
    Solution:

    Given:
    - A is a 2 x 2 matrix
    - The characteristic equation of A is given by 2A^2 - 5A + 2I = 0
    - We need to find the value of 2(Tr A) - 3(det A)

    Characteristic Equation:
    The characteristic equation of a matrix A is given by:
    |A - λI| = 0, where λ is an eigenvalue of A and I is the identity matrix.

    Eigenvalues and Eigenvectors:
    The eigenvalues of a matrix A are the solutions to the characteristic equation. Let's find the eigenvalues of matrix A.

    Given characteristic equation: 2A^2 - 5A + 2I = 0

    We can rewrite the equation as:
    2(A^2 - (5/2)A) = -2I
    (A^2 - (5/2)A) = -I

    Taking determinant on both sides:
    |A^2 - (5/2)A| = -|I|
    |A^2 - (5/2)A| = -1

    The determinant of a product of matrices is equal to the product of determinants. So we can write:
    |A^2 - (5/2)A| = |A^2 - (5/2)A| = -1

    Let λ1 and λ2 be the eigenvalues of matrix A.

    So, the characteristic equation can be written as:
    (λ - λ1)(λ - λ2) = -1

    Expanding the equation, we get:
    λ^2 - (λ1 + λ2)λ + λ1λ2 = -1

    Comparing the coefficients with the characteristic equation, we have:
    λ^2 - (Tr A)λ + det A = 0

    Comparing the above equation with the characteristic equation, we get:
    Tr A = (5/2)
    det A = -1

    Calculating the value of 2(Tr A) - 3(det A):
    Substituting the values of Tr A and det A in the given expression:
    2(Tr A) - 3(det A) = 2(5/2) - 3(-1) = 5 - (-3) = 5 + 3 = 8

    However, the correct answer is given as 2.

    Explanation:
    There seems to be an error in the given answer. The correct value of 2(Tr A) - 3(det A) should be 8, not 2.
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    Consider a 2 x 2 matrix A, whose characteristic equation is given by 2A2 - 5 A + 2I = 0 . Then, the value of 2(Tr A)-3(det A) = ___________Correct answer is '2'. Can you explain this answer?
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    Consider a 2 x 2 matrix A, whose characteristic equation is given by 2A2 - 5 A + 2I = 0 . Then, the value of 2(Tr A)-3(det A) = ___________Correct answer is '2'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Consider a 2 x 2 matrix A, whose characteristic equation is given by 2A2 - 5 A + 2I = 0 . Then, the value of 2(Tr A)-3(det A) = ___________Correct answer is '2'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Consider a 2 x 2 matrix A, whose characteristic equation is given by 2A2 - 5 A + 2I = 0 . Then, the value of 2(Tr A)-3(det A) = ___________Correct answer is '2'. Can you explain this answer?.
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