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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 29

Find each sum or difference, if possible.
[246]+[246]\(\left\)[ \(\begin{matrix}\) 2 & 4 & 6 \(\end{matrix}\) \(\right\)] + \(\left\)[ \(\begin{matrix}\) -2 \\ -4 \\ -6 \(\end{matrix}\) \(\right\)]

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1
Identify the dimensions of the matrices involved. A <3x1> matrix has 3 rows and 1 column, while a <1x3> matrix has 1 row and 3 columns.
Recall that matrix addition or subtraction is only defined when both matrices have the same dimensions (i.e., the same number of rows and columns).
Since the given matrices have different dimensions (<3x1> vs. <1x3>), they cannot be added or subtracted directly.
Therefore, conclude that the sum or difference of these two matrices is not possible due to incompatible dimensions.
If you want to perform operations involving these matrices, consider other operations like matrix multiplication, but addition and subtraction require matching dimensions.

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Key Concepts

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

Matrix Dimensions and Compatibility

Matrix addition and subtraction require the matrices to have the same dimensions, meaning the same number of rows and columns. If the matrices differ in size, their sum or difference is undefined. Understanding this is crucial to determine if the operation is possible.
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Matrix Addition and Subtraction

When two matrices have the same dimensions, their sum or difference is found by adding or subtracting corresponding elements. This operation is performed element-wise, resulting in a new matrix of the same size.
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Matrix Notation and Representation

Matrices are represented by rows and columns, often denoted as m x n, where m is the number of rows and n is the number of columns. Recognizing the notation helps in visualizing the structure and performing operations correctly.
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