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Ch. 6 - Matrices and Determinants
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514당신이 사용하는 게 아니라요?교과서 변경
7장, 문제 13d

In Exercises 9 - 16, find the following matrices: d. - 3A + 2B
Matrices A and B for exercise on matrix operations in college algebra course.

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Step 1: Identify the matrices A and B given in the problem. Matrix A is \( \begin{bmatrix} 2 \\ -4 \\ 1 \end{bmatrix} \) and matrix B is \( \begin{bmatrix} -5 \\ 3 \\ -1 \end{bmatrix} \).
Step 2: Understand the operation to perform: \( -3A + 2B \). This means you will multiply each element of matrix A by -3 and each element of matrix B by 2.
Step 3: Multiply matrix A by -3. Multiply each element of A by -3: \( -3 \times 2 \), \( -3 \times -4 \), and \( -3 \times 1 \).
Step 4: Multiply matrix B by 2. Multiply each element of B by 2: \( 2 \times -5 \), \( 2 \times 3 \), and \( 2 \times -1 \).
Step 5: Add the resulting matrices from steps 3 and 4 element-wise. That is, add the corresponding elements from the two matrices to get the final matrix \( -3A + 2B \).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
3m
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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Matrix Addition and Scalar Multiplication

Matrix addition involves adding corresponding elements of two matrices of the same dimensions. Scalar multiplication means multiplying every element of a matrix by a constant. These operations are fundamental for combining matrices as in the expression -3A + 2B.
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Finding Zeros & Their Multiplicity

Matrix Dimensions and Compatibility

For matrix addition or subtraction, the matrices must have the same dimensions. Here, both A and B are 3x1 matrices, so operations like -3A + 2B are valid. Understanding dimensions ensures correct application of matrix operations.
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4:35
Introduction to Matrices

Order of Operations in Matrix Expressions

When evaluating expressions like -3A + 2B, scalar multiplication is performed first on each matrix, followed by matrix addition. This order ensures accurate computation and avoids errors in combining matrices.
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Performing Row Operations on Matrices