Skip to main content
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 13a

Find the following matrices: A+BA + B
A=[2−41],B=[−53−1]A = \(\begin{bmatrix}\) 2 \\ -4 \\ 1 \(\end{bmatrix}\) , B = \(\begin{bmatrix}\) -5 \\ 3 \\ -1 \(\end{bmatrix}\)

Guida verificata passo dopo passo
1
Identify the given matrices: \( A = \begin{bmatrix} 2 \\ -4 \\ 1 \end{bmatrix} \) and \( B = \begin{bmatrix} -5 \\ 3 \\ -1 \end{bmatrix} \).
Calculate the scalar multiplication of matrix \( B \) by 2: multiply each element of \( B \) by 2 to get \( 2B = \begin{bmatrix} 2 \times (-5) \\ 2 \times 3 \\ 2 \times (-1) \end{bmatrix} \).
Calculate the scalar multiplication of matrix \( A \) by 5: multiply each element of \( A \) by 5 to get \( 5A = \begin{bmatrix} 5 \times 2 \\ 5 \times (-4) \\ 5 \times 1 \end{bmatrix} \).
Calculate the expression \( A + 2B - 5A \) by performing matrix addition and subtraction element-wise: \( A + 2B - 5A = (A - 5A) + 2B = (-4A) + 2B \).
Perform the element-wise operations to combine the matrices: multiply \( A \) by -4, then add the resulting matrix to \( 2B \) to get the final matrix.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
1m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Matrix Addition

Matrix addition involves adding corresponding elements from two matrices of the same dimensions. Each element in the resulting matrix is the sum of elements in the same position from the original matrices. This operation is only defined when both matrices have identical sizes.
Video consigliato:
8:38
Performing Row Operations on Matrices

Scalar Multiplication of a Matrix

Scalar multiplication means multiplying every element of a matrix by a constant (scalar). This operation scales the matrix by the scalar value, changing the magnitude of each element but not the matrix's dimensions.
Video consigliato:
03:42
Finding Zeros & Their Multiplicity

Matrix Dimensions and Compatibility

Understanding matrix dimensions is crucial for performing operations like addition and scalar multiplication. Two matrices can be added only if they have the same number of rows and columns. Scalar multiplication can be applied to any matrix regardless of its size.
Video consigliato:
4:35
Introduction to Matrices