Find the cofactors of the elements of the matrix \(\begin{bmatrix} 2 & -3 \\ 3 & 5 \end{bmatrix}\)

Q.4 Find the cofactors of the elements of the matrix \(\begin{bmatrix} 2 & -3 \\ 3 & 5 \end{bmatrix}\)

Doubtly Asked 28 Oct 2026 Board exam · July 2025 hsc 12th Save WhatsApp Report

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Answer: \(A_{11} = 5,\ A_{12} = -3,\ A_{21} = 3,\ A_{22} = 2\)

Let \(A = \begin{bmatrix} 2 & -3 \\ 3 & 5 \end{bmatrix}\). Cofactor \(A_{ij} = (-1)^{i+j}M_{ij}\).

\(A_{11} = (-1)^2(5) = 5\), \(A_{12} = (-1)^3(3) = -3\), \(A_{21} = (-1)^3(-3) = 3\), \(A_{22} = (-1)^4(2) = 2\).

Doubtly AI · 28 Oct 2026 AI-verified · Oct 2026 Report

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