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2: Matrices

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    202797
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    • 2.1: Matrix Addition, Scalar Multiplication, and Transposition
      This section covers the fundamentals of matrices, including definitions, types, and key operations such as addition, scalar multiplication, and transposition. It emphasizes properties like commutativity, associativity, and the uniqueness of decomposing a matrix into symmetric and skew-symmetric components. Various examples clarify these concepts, along with exercises illustrating specific matrix characteristics and transformations.
    • 2.2: Matrix Multiplication
      This page covers matrix multiplication, focusing on conformability and examples, while addressing properties such as non-commutativity and the identity matrix. It highlights the significance of the standard matrix form in systems of linear equations and presents exercises on multiplying matrices, including diagonal matrices and vector operations.
    • 2.3: The Identity and Inverses
      There is a special matrix, denoted I , which is called to as the identity matrix
    • 2.4: Finding the Inverse of a Matrix
      In Example 2.6.1, we were given A^\(−1\)  and asked to verify that this matrix was in fact the inverse of A. In this section, we explore how to find A\(^−1 \).
    • 2.5: Elementary Matrices
      We now turn our attention to a special type of matrix called an elementary matrix.
    • 2.6: LU Factorization
      An LU factorization of a matrix involves writing the given matrix as the product of a lower triangular matrix (L) which has the main diagonal consisting entirely of ones, and an upper triangular matrix (U) in the indicated order.

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    This page titled 2: Matrices is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Ken Kuttler (Lyryx) via source content that was edited to the style and standards of the LibreTexts platform.