Chapter 10: Problem 26
Find the determinant of the matrix. Determine whether the matrix has an inverse, but don't calculate the inverse. $$\left[\begin{array}{rrr} 0 & -1 & 0 \\ 2 & 6 & 4 \\ 1 & 0 & 3 \end{array}\right]$$
Short Answer
Expert verified
The determinant is 2. The matrix has an inverse.
Step by step solution
01
Write down the formula for the determinant of a 3x3 matrix
The determinant of a 3x3 matrix \( A \) with elements \( a_{ij} \) is calculated using the formula: \[ \text{det}(A) = a_{11}(a_{22}a_{33} - a_{23}a_{32}) - a_{12}(a_{21}a_{33} - a_{23}a_{31}) + a_{13}(a_{21}a_{32} - a_{22}a_{31}) \]
02
Identify the elements of the matrix
For the given matrix: \[ \begin{bmatrix} 0 & -1 & 0 \ 2 & 6 & 4 \ 1 & 0 & 3 \end{bmatrix} \]We identify: \( a_{11} = 0, a_{12} = -1, a_{13} = 0, a_{21} = 2, a_{22} = 6, a_{23} = 4, a_{31} = 1, a_{32} = 0, a_{33} = 3 \)
03
Calculate each of the three terms for the determinant
There are three terms to calculate: 1. \( a_{11}(a_{22}a_{33} - a_{23}a_{32}) = 0(6 \cdot 3 - 4 \cdot 0) = 0 \)2. \( -a_{12}(a_{21}a_{33} - a_{23}a_{31}) = 1(2 \cdot 3 - 4 \cdot 1) = 1(6 - 4) = 1 \cdot 2 = 2 \)3. \( a_{13}(a_{21}a_{32} - a_{22}a_{31}) = 0(2 \cdot 0 - 6 \cdot 1) = 0 \)
04
Sum the terms to find the determinant
The determinant is the sum of the three calculated terms: \[ \text{det}(A) = 0 + 2 + 0 = 2 \]
05
Determine if the matrix has an inverse
A matrix has an inverse if its determinant is not equal to zero. Here, the determinant is 2, which is not zero. Therefore, the matrix does have an inverse.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Matrix Inverse
A matrix inverse is a concept you often come across in linear algebra. Simply put, the inverse of a matrix is another matrix that, when multiplied with the original, results in the identity matrix. To check if a matrix has an inverse, you need to determine its determinant.
- If the determinant is non-zero, the matrix has an inverse.
- If the determinant is zero, the matrix is said to be singular and it does not have an inverse.
3x3 Matrix
A 3x3 matrix is a square matrix consisting of three rows and three columns. It is a common size for matrices in mathematics, often used to represent various transformations and equations in linear algebra. The matrix given in the exercise is:\[\begin{bmatrix} 0 & -1 & 0 \2 & 6 & 4 \1 & 0 & 3 \end{bmatrix}.\]Such matrices are called 3x3 because they have three rows and three columns. The elements of these matrices are addressed using a double subscript notation where the first subscript refers to the row and the second to the column, such as \( a_{11} \) and \( a_{32} \).
- 3x3 matrices are used often because of their size, which is manageable for hand calculations and computational software alike.
Linear Algebra
Linear algebra is a core mathematical discipline that deals with vectors, vector spaces, and the transformation between these spaces using matrices. It provides a framework to understand and solve systems of linear equations, which are crucial in various scientific and engineering applications.
A fundamental aspect of linear algebra involves working with matrices and understanding their properties, like determinants and inverses. A determinant gives a scalar value representing certain properties of a matrix, and it's key in determining matrix invertibility.
A fundamental aspect of linear algebra involves working with matrices and understanding their properties, like determinants and inverses. A determinant gives a scalar value representing certain properties of a matrix, and it's key in determining matrix invertibility.
- Linear transformations: These are mappings represented by matrices that transform vectors from one space to another.
- Vector spaces: Main objects of study in linear algebra, consisting of vectors and their linear combinations.