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Ch. 6 - Matrices and Determinants
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 7, Problema 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.

Guida verificata passo dopo passo
1
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 \( -3A + 2B \).

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