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Ch. 5 - Systems and Matrices
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 6, Problem 41

Let A=[2403]A = \(\left\)[ \(\begin{matrix}\) -2 & 4 \\ 0 & 3 \(\end{matrix}\) \(\right\)] and B=[6240]B = \(\left\)[ \(\begin{matrix}\) -6 & 2 \\ 4 & 0 \(\end{matrix}\) \(\right\)]. Find each of the following.
2A

Verified step by step guidance
1
First, identify the matrix A given in the problem. Since the problem statement is incomplete, ensure you have the matrix A before proceeding.
Recall that multiplying a matrix by a scalar means multiplying every element of the matrix by that scalar. Here, the scalar is 2.
Write the expression for 2A as \(2 \times A\).
Multiply each element of matrix A by 2. For example, if an element in A is \(a_{ij}\), then the corresponding element in 2A will be \(2 \times a_{ij}\).
Write down the resulting matrix after multiplication, which is the matrix 2A.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Matrix Scalar Multiplication

Scalar multiplication involves multiplying every element of a matrix by a constant (scalar). For example, if A is a matrix and k is a scalar, then kA is obtained by multiplying each entry of A by k. This operation changes the magnitude of the matrix but not its dimensions.
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Matrix Notation and Dimensions

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Basic Matrix Operations

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