Use the determinant theorems to evaluate each determinant.∣167067009∣\left| \begin{matrix} 1 & 6 & 7 \\ 0 & 6 & 7 \\ 0 & 0 & 9 \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 53

6장, 문제 53

Use the determinant theorems to evaluate each determinant.
$∣ \begin{matrix} 1 & 6 & 7 \\ 0 & 6 & 7 \\ 0 & 0 & 9 \end{matrix} ∣$

검증된 단계별 안내

Identify the size and structure of the given determinant matrix to understand which determinant theorems can be applied effectively.

Recall key determinant theorems such as: the determinant of a matrix with two identical rows is zero, swapping two rows changes the sign of the determinant, and the determinant of a triangular matrix is the product of its diagonal entries.

Apply row operations that simplify the matrix to a form where the determinant is easier to calculate, keeping track of how each operation affects the determinant value according to the theorems.

Use the properties that multiplying a row by a scalar multiplies the determinant by that scalar, and adding a multiple of one row to another does not change the determinant, to further simplify the matrix if needed.

Once the matrix is in a simplified form (such as upper triangular), calculate the determinant by multiplying the diagonal entries, and adjust the sign or scale of the determinant based on the row operations performed.

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 such as invertibility. It can be calculated using various methods, including expansion by minors or row operations, and is essential for solving systems of equations and understanding matrix behavior.

Determinant Theorems

Determinant theorems are rules that simplify the calculation of determinants, such as the effect of row swaps, scalar multiplication of rows, and adding multiples of one row to another. These theorems help reduce complex matrices to simpler forms without changing or by predictably changing the determinant.

Row Operations and Their Impact on Determinants

Certain row operations affect the determinant in specific ways: swapping two rows multiplies the determinant by -1, multiplying a row by a scalar multiplies the determinant by that scalar, and adding a multiple of one row to another does not change the determinant. Understanding these effects is crucial for efficient determinant evaluation.

Use the determinant theorems to evaluate each determinant.∣167067009∣\(\left\)| \(\begin{matrix}\) 1 & 6 & 7 \\ 0 & 6 & 7 \\ 0 & 0 & 9 \(\end{matrix}\) \(\right\)|