Evaluate each determinant.∣4−78213−630∣\left| \begin{matrix} 4 & -7 & 8 \\ 2 & 1 & 3 \\ -6 & 3 & 0 \end{matrix} \right|

Ch. 5 - Systems and Matrices

Lial13th EditionCollege AlgebraISBN: 9780136881063당신이 사용하는 게 아니라요?교과서 변경

모든 교과서

Lial 13th Edition

Ch. 5 - Systems and Matrices

문제 21

6장, 문제 21

Evaluate each determinant.
$∣ \begin{matrix} 4 & - 7 & 8 \\ 2 & 1 & 3 \\ - 6 & 3 & 0 \end{matrix} ∣$

검증된 단계별 안내

Identify the size of the determinant matrix (e.g., 2x2, 3x3) to determine the appropriate method for evaluation.

For a 2x2 matrix $\begin{bmatrix} a & b \\ c & d \end{bmatrix}$, use the formula for the determinant: $\det = ad - bc$.

For a 3x3 matrix $\begin{bmatrix} a & b & c \\ d & e & f \\ g & h & i \end{bmatrix}$, apply the rule of Sarrus or cofactor expansion to find the determinant.

If using cofactor expansion, select a row or column (usually one with zeros for simplicity), then calculate the minors and cofactors for each element in that row or column.

Sum the products of each element and its corresponding cofactor to get the determinant value: $\det = a_{ij}C_{ij} + a_{ik}C_{ik} + \dots$ where $C_{ij}$ are cofactors.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

도움이 되었나요?

주요 개념

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

Determinant of a Matrix

The determinant is a scalar value computed from a square matrix that provides important properties about the matrix, such as invertibility. For a 2x2 matrix, it is calculated as ad - bc, where a, b, c, and d are the elements of the matrix. Determinants help in solving systems of linear equations and understanding matrix behavior.

Methods for Calculating Determinants

Determinants can be calculated using various methods depending on the matrix size, including expansion by minors, cofactor expansion, and row reduction. For larger matrices, breaking down into smaller matrices or using properties like linearity simplifies the process. Understanding these methods is essential for efficient evaluation.

Properties of Determinants

Determinants have key properties such as changing sign when two rows are swapped, being zero if rows are linearly dependent, and the determinant of a product equals the product of determinants. These properties aid in simplifying calculations and interpreting the results in algebraic contexts.

Evaluate each determinant.∣4−78213−630∣\(\left\)| \(\begin{matrix}\) 4 & -7 & 8 \\ 2 & 1 & 3 \\ -6 & 3 & 0 \(\end{matrix}\) \(\right\)|