问题

Find the characteristic polynomial of the following matrix:\n$\left(\n\begin{array}{ccc}\n -9 & -5 & 7 \\\n -4 & -11 & 11 \\\n 5 & 3 & 12 \\\n\end{array}\n\right)$. Please put your final answer in a $\\boxed{}$.

答案

模型 模型答案 正确答案
金声玉亮2.0 To find the characteristic polynomial of the given matrix, we need to compute the determinant of the matrix \( A - \lambda I \), where \( A \) is the given matrix and \( I \) is the identity matrix. The matrix \( A \) is:

\[
A = \left(
\begin{array}{ccc}
-9 & -5 & 7 \\
-4 & -11 & 11 \\
5 & 3 & 12 \\
\end{array}
\right)
\]

First, we form the matrix \( A - \lambda I \):

\[
A - \lambda I = \left(
\begin{array}{ccc}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda \\
\end{array}
\right)
\]

Next, we compute the determinant of \( A - \lambda I \):

\[
\det(A - \lambda I) = \det \left(
\begin{array}{ccc}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda \\
\end{array}
\right)
\]

We expand this determinant along the first row:

\[
\det(A - \lambda I) = (-9 - \lambda) \det \left(
\begin{array}{cc}
-11 - \lambda & 11 \\
3 & 12 - \lambda \\
\end{array}
\right)
- (-5) \det \left(
\begin{array}{cc}
-4 & 11 \\
5 & 12 - \lambda \\
\end{array}
\right)
+ 7 \det \left(
\begin{array}{cc}
-4 & -11 - \lambda \\
5 & 3 \\
\end{array}
\right)
\]

We compute each of the 2x2 determinants:

1. \[
\det \left(
\begin{array}{cc}
-11 - \lambda & 11 \\
3 & 12 - \lambda \\
\end{array}
\right) = (-11 - \lambda)(12 - \lambda) - (11)(3) = 132 + 11\lambda - 12\lambda - \lambda^2 - 33 = -\lambda^2 - \lambda + 99
\]

2. \[
\det \left(
\begin{array}{cc}
-4 & 11 \\
5 & 12 - \lambda \\
\end{array}
\right) = (-4)(12 - \lambda) - (11)(5) = -48 + 4\lambda - 55 = 4\lambda - 103
\]

3. \[
\det \left(
\begin{array}{cc}
-4 & -11 - \lambda \\
5 & 3 \\
\end{array}
\right) = (-4)(3) - (-11 - \lambda)(5) = -12 + 55 + 5\lambda = 43 + 5\lambda
\]

Substituting these back into the determinant expansion:

\[
\det(A - \lambda I) = (-9 - \lambda)(-\lambda^2 - \lambda + 99) + 5(4\lambda - 103) + 7(43 + 5\lambda)
\]

Expanding each term:

\[
(-9 - \lambda)(-\lambda^2 - \lambda + 99) = 9\lambda^2 + 9\lambda - 891 + \lambda^3 + \lambda^2 - 99\lambda = \lambda^3 + 10\lambda^2 - 90\lambda - 891
\]

\[
5(4\lambda - 103) = 20\lambda - 515
\]

\[
7(43 + 5\lambda) = 301 + 35\lambda
\]

Combining all terms:

\[
\det(A - \lambda I) = \lambda^3 + 10\lambda^2 - 90\lambda - 891 + 20\lambda - 515 + 301 + 35\lambda
\]

Simplifying:

\[
\det(A - \lambda I) = \lambda^3 + 10\lambda^2 - 35\lambda - 1105
\]

Thus, the characteristic polynomial is:

\[
\boxed{\lambda^3 + 10\lambda^2 - 35\lambda - 1105}
\]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
deepseek-r1

To find the characteristic polynomial of the matrix

\[
A = \begin{pmatrix}
-9 & -5 & 7 \\
-4 & -11 & 11 \\
5 & 3 & 12
\end{pmatrix},
\]

we need to compute the determinant of \(A - \lambda I\). The matrix \(A - \lambda I\) is:

\[
\begin{pmatrix}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda
\end{pmatrix}.
\]

Using the cofactor expansion along the first row, we calculate the determinant:

1. **First minor (M11):**
\[
\det\begin{pmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{pmatrix} = (-11 - \lambda)(12 - \lambda) - 33 = \lambda^2 - \lambda - 165.
\]

2. **Second minor (M12):**
\[
\det\begin{pmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{pmatrix} = (-4)(12 - \lambda) - 55 = 4\lambda - 103.
\]

3. **Third minor (M13):**
\[
\det\begin{pmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{pmatrix} = -12 + 5(\lambda + 11) = 5\lambda + 43.
\]

Putting it all together, the determinant of \(A - \lambda I\) is:

\[
(-9 - \lambda)(\lambda^2 - \lambda - 165) + 5(4\lambda - 103) + 7(5\lambda + 43).
\]

Expanding and simplifying:

1. **First term:**
\[
(-9 - \lambda)(\lambda^2 - \lambda - 165) = -\lambda^3 - 8\lambda^2 + 174\lambda + 1485.
\]

2. **Second term:**
\[
5(4\lambda - 103) = 20\lambda - 515.
\]

3. **Third term:**
\[
7(5\lambda + 43) = 35\lambda + 301.
\]

Combining all terms:

\[
-\lambda^3 - 8\lambda^2 + 174\lambda + 1485 + 20\lambda - 515 + 35\lambda + 301.
\]

Simplifying further:

\[
-\lambda^3 - 8\lambda^2 + 229\lambda + 1271.
\]

To convert this to the characteristic polynomial in the standard form \(\det(\lambda I - A)\), we multiply by -1:

\[
\lambda^3 + 8\lambda^2 - 229\lambda - 1271.
\]

Thus, the characteristic polynomial of the matrix is

\[
\boxed{x^3 + 8x^2 - 229x - 1271}.
\]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
gpto1 To find the characteristic polynomial \(P(\lambda)\) of the matrix \(A\), we compute the determinant of \(A - \lambda I\), where \(I\) is the identity matrix:

\[
A - \lambda I = \begin{pmatrix} -9 - \lambda & -5 & 7 \\ -4 & -11 - \lambda & 11 \\ 5 & 3 & 12 - \lambda \end{pmatrix}
\]

The characteristic polynomial is:

\[
P(\lambda) = \det(A - \lambda I)
\]

Using cofactor expansion along the first row, we have:

\[
P(\lambda) = (-9 - \lambda) \det\begin{pmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{pmatrix} - (-5) \det\begin{pmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{pmatrix} + 7 \det\begin{pmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{pmatrix}
\]

Calculate each determinant:

1. \(\det\begin{pmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{pmatrix} = (-11 - \lambda)(12 - \lambda) - (11)(3) = (\lambda^2 - \lambda - 165)\)
2. \(\det\begin{pmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{pmatrix} = (-4)(12 - \lambda) - (11)(5) = (-103 + 4\lambda)\)
3. \(\det\begin{pmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{pmatrix} = (-4)(3) - (-11 - \lambda)(5) = (43 + 5\lambda)\)

Now, substitute back into \(P(\lambda)\):

\[
P(\lambda) = (-9 - \lambda)(\lambda^2 - \lambda - 165) + 5(-103 + 4\lambda) + 7(43 + 5\lambda)
\]

Simplify the expression:

\[
\begin{align*}
P(\lambda) &= (-9 - \lambda)(\lambda^2 - \lambda - 165) + 5(-103 + 4\lambda) + 7(43 + 5\lambda) \\
&= -(\lambda^3 + 8\lambda^2 - 229\lambda - 1271)
\end{align*}
\]

Finally, write the characteristic polynomial:

\[
P(\lambda) = \lambda^3 + 8\lambda^2 - 229\lambda - 1271
\]

\[\boxed{\lambda^{3} + 8\lambda^{2} -229\lambda\ -\ 1271}\]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
gpt-4o-2024-08-06 To find the characteristic polynomial of the matrix

\[
A = \begin{pmatrix} -9 & -5 & 7 \\ -4 & -11 & 11 \\ 5 & 3 & 12 \end{pmatrix},
\]

we need to compute the determinant of the matrix \( A - \lambda I \), where \( I \) is the identity matrix and \( \lambda \) is a scalar. The matrix \( A - \lambda I \) is:

\[
A - \lambda I = \begin{pmatrix} -9 - \lambda & -5 & 7 \\ -4 & -11 - \lambda & 11 \\ 5 & 3 & 12 - \lambda \end{pmatrix}.
\]

The characteristic polynomial is given by the determinant:

\[
\det(A - \lambda I) = \begin{vmatrix} -9 - \lambda & -5 & 7 \\ -4 & -11 - \lambda & 11 \\ 5 & 3 & 12 - \lambda \end{vmatrix}.
\]

We can calculate this determinant using the cofactor expansion along the first row:

\[
\det(A - \lambda I) = (-9 - \lambda) \begin{vmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{vmatrix} - (-5) \begin{vmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{vmatrix} + 7 \begin{vmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{vmatrix}.
\]

Now, we compute each of these 2x2 determinants:

1. \(\begin{vmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{vmatrix} = (-11 - \lambda)(12 - \lambda) - (11)(3)\).

\[
= (-11 - \lambda)(12 - \lambda) - 33 = (121 + 11\lambda + 12\lambda + \lambda^2) - 33 = \lambda^2 + 23\lambda + 88.
\]

2. \(\begin{vmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{vmatrix} = (-4)(12 - \lambda) - (11)(5)\).

\[
= -48 + 4\lambda - 55 = 4\lambda - 103.
\]

3. \(\begin{vmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{vmatrix} = (-4)(3) - (-11 - \lambda)(5)\).

\[
= -12 + 55 + 5\lambda = 5\lambda + 43.
\]

Substituting these back into the cofactor expansion:

\[
\det(A - \lambda I) = (-9 - \lambda)(\lambda^2 + 23\lambda + 88) + 5(4\lambda - 103) + 7(5\lambda + 43).
\]

Expanding each term:

- The first term:
\[
(-9 - \lambda)(\lambda^2 + 23\lambda + 88) = -9(\lambda^2 + 23\lambda + 88) - \lambda(\lambda^2 + 23\lambda + 88).
\]
\[
= -9\lambda^2 - 207\lambda - 792 - \lambda^3 - 23\lambda^2 - 88\lambda.
\]
\[
= -\lambda^3 - 32\lambda^2 - 295\lambda - 792.
\]

- The second term:
\[
5(4\lambda - 103) = 20\lambda - 515.
\]

- The third term:
\[
7(5\lambda + 43) = 35\lambda + 301.
\]

Combining all terms:

\[
-\lambda^3 - 32\lambda^2 - 295\lambda - 792 + 20\lambda - 515 + 35\lambda + 301.
\]

Combine like terms:

- \(\lambda^3\) term: \(-\lambda^3\).
- \(\lambda^2\) term: \(-32\lambda^2\).
- \(\lambda\) term: \(-295\lambda + 20\lambda + 35\lambda = -240\lambda\).
- Constant term: \(-792 - 515 + 301 = -1006\).

Thus, the characteristic polynomial is:

\[
\boxed{-\lambda^3 - 32\lambda^2 - 240\lambda - 1006}.
\]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
DeepSeek-Coder-V2-Lite-Instruct To find the characteristic polynomial of the given matrix, we will use the formula for the characteristic polynomial of a 3x3 matrix \( A \), which is given by:

\[
\text{det}(A - \lambda I)
\]

where \( \lambda \) is a scalar and \( I \) is the identity matrix of the same size. For the given matrix:

\[
A = \left(
\begin{array}{ccc}
-9 & -5 & 7 \\
-4 & -11 & 11 \\
5 & 3 & 12 \\
\end{array}
\right)
\]

we need to compute the determinant of \( A - \lambda I \):

\[
A - \lambda I = \left(
\begin{array}{ccc}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda \\
\end{array}
\right)
\]

We will expand the determinant along the first row:

\[
\text{det}(A - \lambda I) = (-9 - \lambda) \left|
\begin{array}{cc}
-11 - \lambda & 11 \\
3 & 12 - \lambda \\
\end{array}
\right| - (-5) \left|
\begin{array}{cc}
-4 & 11 \\
5 & 12 - \lambda \\
\end{array}
\right| + 7 \left|
\begin{array}{cc}
-4 & -11 - \lambda \\
5 & 3 \\
\end{array}
\right|
\]

First, we compute the 2x2 determinants:

\[
\left|
\begin{array}{cc}
-11 - \lambda & 11 \\
3 & 12 - \lambda \\
\end{array}
\right| = (-11 - \lambda)(12 - \lambda) - (11)(3) = -11 \cdot 12 + \lambda \cdot 12 - \lambda \cdot 11 - \lambda^2 - 33 = -132 + 12\lambda - 11\lambda - \lambda^2 - 33 = -\lambda^2 + \lambda - 165
\]

\[
\left|
\begin{array}{cc}
-4 & 11 \\
5 & 12 - \lambda \\
\end{array}
\right| = (-4)(12 - \lambda) - (11)(5) = -48 + 4\lambda - 55 = 4\lambda - 103
\]

\[
\left|
\begin{array}{cc}
-4 & -11 - \lambda \\
5 & 3 \\
\end{array}
\right| = (-4)(3) - (-11 - \lambda)(5) = -12 + 55 + 5\lambda = 43 + 5\lambda
\]

Now, substituting these back into the determinant expansion:

\[
\text{det}(A - \lambda I) = (-9 - \lambda)(-\lambda^2 + \lambda - 165) - (-5)(4\lambda - 103) + 7(43 + 5\lambda)
\]

Expanding and simplifying:

\[
= (-9 - \lambda)(-\lambda^2 + \lambda - 165) + 20\lambda - 515 + 301 + 35\lambda
\]

\[
= \lambda^3 + 9\lambda^2 + 15\lambda + 1485 + 20\lambda - 515 + 301 + 35\lambda
\]

\[
= \lambda^3 + 9\lambda^2 + 65\lambda + 1271
\]

Thus, the characteristic polynomial is:

\[
\boxed{\lambda^3 + 9\lambda^2 + 65\lambda + 1271}
\]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
Meta-Llama-3.1-405B-Instruct-Turbo ## Step 1: To find the characteristic polynomial of the given matrix, we first need to understand what the characteristic polynomial is. It is defined as the determinant of the matrix obtained by subtracting a variable, usually denoted as lambda (λ), from the diagonal elements of the original matrix.

## Step 2: The given matrix is a 3x3 matrix. To find its characteristic polynomial, we will subtract λ from the diagonal elements and then calculate the determinant of the resulting matrix.

## Step 3: The original matrix is:
$\left(\n\begin{array}{ccc}\n -9 & -5 & 7 \\\n -4 & -11 & 11 \\\n 5 & 3 & 12 \\\n\end{array}\n\right)$. Subtracting λ from the diagonal elements, we get:
$\left(\n\begin{array}{ccc}\n -9-λ & -5 & 7 \\\n -4 & -11-λ & 11 \\\n 5 & 3 & 12-λ \\\n\end{array}\n\right)$.

## Step 4: Now, we calculate the determinant of this matrix by expanding along the first row. The determinant is given by:
$(-9-λ) \times \left((-11-λ) \times (12-λ) - 11 \times 3\right) - (-5) \times \left((-4) \times (12-λ) - 11 \times 5\right) + 7 \times \left((-4) \times 3 - (-11-λ) \times 5\right)$.

## Step 5: Expanding and simplifying the expression from Step 4 will give us the characteristic polynomial of the matrix.

## Step 6: After expanding and simplifying, we get the characteristic polynomial as a cubic polynomial in terms of λ.

## Step 7: The characteristic polynomial is:
$(-9-λ) \times ((-11-λ) \times (12-λ) - 33) + 5 \times ((-4) \times (12-λ) + 55) + 7 \times ((-4) \times 3 + 5 \times (-11-λ))$.

## Step 8: Further simplification is needed to put the polynomial in the standard form.

## Step 9: After simplifying and combining like terms, we should have the characteristic polynomial in the form $aλ^3 + bλ^2 + cλ + d$.

## Step 10: Calculating the determinant with the given matrix and λ, we find the characteristic polynomial.

## Step 11: The characteristic polynomial after simplification is $-λ^3 - 12λ^2 + 13λ + 1380$.


The final answer is: $\boxed{-λ^3 - 12λ^2 + 13λ + 1380}$
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
Meta-Llama-3.1-70B-Instruct-Turbo ## Step 1: Understand the problem
To find the characteristic polynomial of the given matrix, we need to calculate the determinant of the matrix $A - \lambda I$, where $A$ is the given matrix, $\lambda$ is the eigenvalue, and $I$ is the identity matrix.

## Step 2: Write down the matrix $A - \lambda I$
The matrix $A - \lambda I$ is given by:
$\left(\begin{array}{ccc} -9-\lambda & -5 & 7 \\ -4 & -11-\lambda & 11 \\ 5 & 3 & 12-\lambda \end{array}\right)$.

## Step 3: Calculate the determinant of $A - \lambda I$
Using the formula for the determinant of a 3x3 matrix, we get:
$\det(A - \lambda I) = (-9-\lambda)((-11-\lambda)(12-\lambda) - 11*3) - (-5)((-4)(12-\lambda) - 11*5) + 7((-4)*3 - (-11-\lambda)*5)$.

## Step 4: Expand and simplify the determinant
Expanding and simplifying the determinant, we get:
$\det(A - \lambda I) = (-9-\lambda)(-132 + 11\lambda - \lambda^2 - 33) + 5(-48 + 4\lambda - 55) + 7(-12 + 55 + 5\lambda)$.

## Step 5: Further simplify the determinant
Further simplifying the determinant, we get:
$\det(A - \lambda I) = (-9-\lambda)(-165 + 11\lambda - \lambda^2) + 5(-103 + 4\lambda) + 7(43 + 5\lambda)$.

## Step 6: Multiply and combine like terms
Multiplying and combining like terms, we get:
$\det(A - \lambda I) = 1485 - 99\lambda + 9\lambda^2 - 11\lambda^2 + \lambda^3 - 515 + 20\lambda + 301 + 35\lambda$.

## Step 7: Combine like terms and simplify
Combining like terms and simplifying, we get:
$\det(A - \lambda I) = \lambda^3 - 2\lambda^2 - 44\lambda + 1271$.

The final answer is: $\boxed{\lambda^3 - 2\lambda^2 - 44\lambda + 1271}$
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
Qwen2-72B-Instruct To find the characteristic polynomial of a matrix, we need to compute the determinant of $(A-\lambda I)$, where $A$ is the given matrix and $\lambda$ is an eigenvalue. The characteristic polynomial will be a function of $\lambda$, and its roots will give us the eigenvalues of the matrix.

Given matrix $A$:

$$
A = \left(\begin{array}{ccc}
-9 & -5 & 7 \\
-4 & -11 & 11 \\
5 & 3 & 12 \\
\end{array}\right)
$$

We need to find the determinant of $(A-\lambda I)$, where $I$ is the identity matrix of size 3:

$$
A-\lambda I = \left(\begin{array}{ccc}
-9-\lambda & -5 & 7 \\
-4 & -11-\lambda & 11 \\
5 & 3 & 12-\lambda \\
\end{array}\right)
$$

The determinant of this matrix is:

$$
\det(A-\lambda I) = (-9-\lambda)((-11-\lambda)(12-\lambda)-33) + 5((-4)(12-\lambda)+55) + 7(-20-(-11-\lambda)5)
$$

Simplifying this expression gives us the characteristic polynomial:

$$
\det(A-\lambda I) = (-9-\lambda)((-11-\lambda)(12-\lambda)-33) + 5(48-4\lambda+55) + 7(-20+55+5\lambda)
$$

$$
= (-9-\lambda)(-132+11\lambda+\lambda^2-33) + 5(103-4\lambda) + 7(35+5\lambda)
$$

$$
= (-9-\lambda)(\lambda^2+11\lambda-165) + 515-20\lambda + 245 + 35\lambda
$$

$$
= (-9-\lambda)(\lambda^2+11\lambda-165) + 760 + 15\lambda
$$

$$
= -\lambda^3 - 9\lambda^2 - 11\lambda^2 - 99\lambda + 1485 + 760 + 15\lambda
$$

$$
= -\lambda^3 - 20\lambda^2 - 84\lambda + 2245
$$

So, the characteristic polynomial of the given matrix is:

$$
p(\lambda) = -\lambda^3 - 20\lambda^2 - 84\lambda + 2245
$$

Therefore, the final answer is $\boxed{-\lambda^3 - 20\lambda^2 - 84\lambda + 2245}$.
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
baichuan4 To find the characteristic polynomial of a matrix, we need to compute the determinant of the matrix minus $x$ times the identity matrix. The identity matrix is a square matrix with ones on the diagonal and zeros everywhere else.

Given the matrix $A$:
$$
A = \left(\n\begin{array}{ccc}
-9 & -5 & 7 \\
-4 & -11 & 11 \\
5 & 3 & 12 \\
\end{array}\n\right)
$$

We first construct the matrix $A - xI$, where $I$ is the $3 \times 3$ identity matrix:
$$
A - xI = \left(\n\begin{array}{ccc}
-9-x & -5 & 7 \\
-4 & -11-x & 11 \\
5 & 3 & 12-x \\
\end{array}\n\right)
$$

Now, we compute the determinant of this matrix:
$$
\det(A - xI) = \left|\n\begin{array}{ccc}
-9-x & -5 & 7 \\
-4 & -11-x & 11 \\
5 & 3 & 12-x \\
\end{array}\n\right|
$$

Using the Laplace expansion or any other method to compute the determinant, we get:
$$
\det(A - xI) = (-9-x)\left|\n\begin{array}{cc}
-11-x & 11 \\
3 & 12-x \\
\end{array}\n\right|
- (-5)\left|\n\begin{array}{cc}
-4 & 11 \\
5 & 12-x \\
\end{array}\n\right|
+ 7\left|\n\begin{array}{cc}
-4 & -11-x \\
5 & 3 \\
\end{array}\n\right|
$$

Computing these smaller determinants, we have:
$$
\det(A - xI) = (-9-x)((-11-x)(12-x) - 33) - (-5)((-4)(12-x) - 55) + 7((-4)(3) - (-11-x)(5))
$$

Expanding and simplifying, we get:
$$
\det(A - xI) = (-9-x)(x^2 + 23x + 132 - 33) + 5(48 - 4x + 55) - 7(12 + 5x + 55)
$$

Further simplification gives:
$$
\det(A - xI) = (-9-x)(x^2 + 23x + 99) + 5(103 - 4x) - 7(67 + 5x)
$$

Distributing and combining like terms, we finally obtain the characteristic polynomial:
$$
\det(A - xI) = -x^3 - 32x^2 - 377x - 1287
$$

This is the characteristic polynomial of the given matrix. We can put it in a box as requested:
$$
\boxed{-x^3 - 32x^2 - 377x - 1287}
$$
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
doubao The characteristic polynomial of a 3x3 matrix $A = \begin{pmatrix}a & b & c\\d & e & f\\g & h & i\end{pmatrix}$ is given by $|A - \lambda I| = \begin{vmatrix}a - \lambda & b & c\\d & e - \lambda & f\\g & h & i - \lambda\end{vmatrix}$.

For the given matrix $\begin{pmatrix}-9 & -5 & 7\\-4 & -11 & 11\\5 & 3 & 12\end{pmatrix}$, the characteristic polynomial is:

\[
\begin{align*}
&\begin{vmatrix}-9 - \lambda & -5 & 7\\-4 & -11 - \lambda & 11\\5 & 3 & 12 - \lambda\end{vmatrix}\\
=& (-9 - \lambda)\begin{vmatrix}-11 - \lambda & 11\\3 & 12 - \lambda\end{vmatrix} - (-5)\begin{vmatrix}-4 & 11\\5 & 12 - \lambda\end{vmatrix} + 7\begin{vmatrix}-4 & -11 - \lambda\\5 & 3\end{vmatrix}\\
=& (-9 - \lambda)[(-11 - \lambda)(12 - \lambda) - 33] - (-5)[-4(12 - \lambda) - 55] + 7[-12 + 5(-11 - \lambda)]\\
=& (-9 - \lambda)[132 + 11\lambda - 12\lambda - \lambda^2 - 33] - (-5)[-48 + 4\lambda - 55] + 7[-12 - 55 - 5\lambda]\\
=& (-9 - \lambda)(99 - \lambda - \lambda^2) + 5(-103 + 4\lambda) + 7(-67 - 5\lambda)\\
=& -891 + 9\lambda + 9\lambda^2 - 99\lambda + \lambda^2 + \lambda^3 - 515 + 20\lambda - 469 - 35\lambda + 7\lambda^2\\
=& \lambda^3 + 17\lambda^2 - 105\lambda - 1875
\end{align*}
\]

So the answer is $\boxed{\lambda^3 + 17\lambda^2 - 105\lambda - 1875}$.
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
gpto1 To find the characteristic polynomial \(P(\lambda)\) of the matrix \(A\), we compute the determinant of \(A - \lambda I\), where \(I\) is the identity matrix:

\[
A - \lambda I = \begin{pmatrix} -9 - \lambda & -5 & 7 \\ -4 & -11 - \lambda & 11 \\ 5 & 3 & 12 - \lambda \end{pmatrix}
\]

The characteristic polynomial is:

\[
P(\lambda) = \det(A - \lambda I)
\]

Using cofactor expansion along the first row, we have:

\[
P(\lambda) = (-9 - \lambda) \det\begin{pmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{pmatrix} - (-5) \det\begin{pmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{pmatrix} + 7 \det\begin{pmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{pmatrix}
\]

Calculate each determinant:

1. \(\det\begin{pmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{pmatrix} = (-11 - \lambda)(12 - \lambda) - (11)(3) = (\lambda^2 - \lambda - 165)\)
2. \(\det\begin{pmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{pmatrix} = (-4)(12 - \lambda) - (11)(5) = (-103 + 4\lambda)\)
3. \(\det\begin{pmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{pmatrix} = (-4)(3) - (-11 - \lambda)(5) = (43 + 5\lambda)\)

Now, substitute back into \(P(\lambda)\):

\[
P(\lambda) = (-9 - \lambda)(\lambda^2 - \lambda - 165) + 5(-103 + 4\lambda) + 7(43 + 5\lambda)
\]

Simplify the expression:

\[
\begin{align*}
P(\lambda) &= (-9 - \lambda)(\lambda^2 - \lambda - 165) + 5(-103 + 4\lambda) + 7(43 + 5\lambda) \\
&= -(\lambda^3 + 8\lambda^2 - 229\lambda - 1271)
\end{align*}
\]

Finally, write the characteristic polynomial:

\[
P(\lambda) = \lambda^3 + 8\lambda^2 - 229\lambda - 1271
\]

\[\boxed{\lambda^{3} + 8\lambda^{2} -229\lambda\ -\ 1271}\]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
kimi To find the characteristic polynomial of a matrix, we need to compute the determinant of the matrix \( A - \lambda I \), where \( A \) is the given matrix, \( \lambda \) is a scalar, and \( I \) is the identity matrix of the same size as \( A \).

Given matrix \( A \):
\[
A = \left(\begin{array}{ccc}
-9 & -5 & 7 \\
-4 & -11 & 11 \\
5 & 3 & 12 \\
\end{array}\right)
\]

The identity matrix \( I \) of size 3x3 is:
\[
I = \left(\begin{array}{ccc}
1 & 0 & 0 \\
0 & 1 & 0 \\
0 & 0 & 1 \\
\end{array}\right)
\]

Thus, \( A - \lambda I \) is:
\[
A - \lambda I = \left(\begin{array}{ccc}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda \\
\end{array}\right)
\]

The characteristic polynomial is given by the determinant of \( A - \lambda I \):
\[
\det(A - \lambda I) = \left| \begin{array}{ccc}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda \\
\end{array} \right|
\]

We will compute this determinant using cofactor expansion along the first row:
\[
\det(A - \lambda I) = (-9 - \lambda) \left| \begin{array}{cc}
-11 - \lambda & 11 \\
3 & 12 - \lambda \\
\end{array} \right|
- (-5) \left| \begin{array}{cc}
-4 & 11 \\
5 & 12 - \lambda \\
\end{array} \right|
+ 7 \left| \begin{array}{cc}
-4 & -11 - \lambda \\
5 & 3 \\
\end{array} \right|
\]

Now, we compute each of the 2x2 determinants:
\[
\left| \begin{array}{cc}
-11 - \lambda & 11 \\
3 & 12 - \lambda \\
\end{array} \right| = (-11 - \lambda)(12 - \lambda) - (11)(3) = \lambda^2 - \lambda - 99
\]

\[
\left| \begin{array}{cc}
-4 & 11 \\
5 & 12 - \lambda \\
\end{array} \right| = (-4)(12 - \lambda) - (11)(5) = 4\lambda - 68
\]

\[
\left| \begin{array}{cc}
-4 & -11 - \lambda \\
5 & 3 \\
\end{array} \right| = (-4)(3) - (-11 - \lambda)(5) = 5\lambda + 29
\]

Substituting these back into the cofactor expansion:
\[
\det(A - \lambda I) = (-9 - \lambda)(\lambda^2 - \lambda - 99) + 5(4\lambda - 68) + 7(5\lambda + 29)
\]

Expanding each term:
\[
(-9 - \lambda)(\lambda^2 - \lambda - 99) = -9\lambda^2 + 9\lambda + 891 - \lambda^3 + \lambda^2 + 99\lambda = -\lambda^3 - 8\lambda^2 + 108\lambda + 891
\]

\[
5(4\lambda - 68) = 20\lambda - 340
\]

\[
7(5\lambda + 29) = 35\lambda + 203
\]

Combining all terms:
\[
-\lambda^3 - 8\lambda^2 + 108\lambda + 891 + 20\lambda - 340 + 35\lambda + 203 = -\lambda^3 - 8\lambda^2 + 163\lambda + 754
\]

Thus, the characteristic polynomial is:
\[
\boxed{-\lambda^3 - 8\lambda^2 + 163\lambda + 754}
\]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
minimax To find the characteristic polynomial of the given matrix, we need to compute the determinant of $A - \lambda I$, where $A$ is the matrix in question and $I$ is the identity matrix of the same size, and $\lambda$ represents the eigenvalues.

The matrix $A - \lambda I$ is:

$$
A - \lambda I = \left(\begin{array}{ccc}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda \\
\end{array}\right)
$$

The characteristic polynomial is given by the determinant of this matrix:

$$
\det(A - \lambda I) = \begin{vmatrix}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda \\
\end{vmatrix}
$$

We can expand this determinant using the rule of Sarrus or the cofactor expansion along any row or column. For simplicity, let's expand along the first column:

$$
\det(A - \lambda I) = (-9 - \lambda)
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
wenxinyiyan To find the characteristic polynomial of the given matrix, we first need to find the determinant of the matrix $A - \lambda I$, where $A$ is the given matrix, $\lambda$ is the eigenvalue, and $I$ is the identity matrix.

Given matrix:
$A = \begin{pmatrix} -9 & -5 & 7 \\ -4 & -11 & 11 \\ 5 & 3 & 12 \end{pmatrix}$

Identity matrix:
$I = \begin{pmatrix} 1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{pmatrix}$

$A - \lambda I = \begin{pmatrix} -9 - \lambda & -5 & 7 \\ -4 & -11 - \lambda & 11 \\ 5 & 3 & 12 - \lambda \end{pmatrix}$

Now, we find the determinant of $A - \lambda I$ using the cofactor expansion method along the first row:

$|A - \lambda I| = (-9 - \lambda) \begin{vmatrix} -11 - \lambda & 11 \\ 3 & 12 - \lambda \end{vmatrix} + 5 \begin{vmatrix} -4 & 11 \\ 5 & 12 - \lambda \end{vmatrix} + 7 \begin{vmatrix} -4 & -11 - \lambda \\ 5 & 3 \end{vmatrix}$

$= (-9 - \lambda)[(-11 - \lambda)(12 - \lambda) - 33] + 5[-4(12 - \lambda) - 55] + 7[-4 \times 3 - 5(-11 - \lambda)]$

$= (-9 - \lambda)(\lambda^2 + \lambda - 132) + 5(4\lambda - 91) + 7(55 + 5\lambda)$

$= -\lambda^3 - 10\lambda^2 + 128\lambda - 49$

So, the characteristic polynomial of the given matrix is:

$\boxed{-\lambda^3 - 10\lambda^2 + 128\lambda - 49}$
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
zhipu To find the characteristic polynomial of a matrix \( A \), we need to compute the determinant of \( A - \lambda I \), where \( \lambda \) is an eigenvalue and \( I \) is the identity matrix of the same size as \( A \).

Given the matrix:
\[ A = \begin{pmatrix}
-9 & -5 & 7 \\
-4 & -11 & 11 \\
5 & 3 & 12
\end{pmatrix} \]

We form the matrix \( A - \lambda I \):
\[ A - \lambda I = \begin{pmatrix}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda
\end{pmatrix} \]

Next, we compute the determinant of \( A - \lambda I \):
\[ \text{det}(A - \lambda I) = \begin{vmatrix}
-9 - \lambda & -5 & 7 \\
-4 & -11 - \lambda & 11 \\
5 & 3 & 12 - \lambda
\end{vmatrix} \]

We can use the cofactor expansion along the first row:
\[ \text{det}(A - \lambda I) = (-9 - \lambda) \begin{vmatrix}
-11 - \lambda & 11 \\
3 & 12 - \lambda
\end{vmatrix} - (-5) \begin{vmatrix}
-4 & 11 \\
5 & 12 - \lambda
\end{vmatrix} + 7 \begin{vmatrix}
-4 & -11 - \lambda \\
5 & 3
\end{vmatrix} \]

Now, we compute each of the 2x2 determinants:
\[ \begin{vmatrix}
-11 - \lambda & 11 \\
3 & 12 - \lambda
\end{vmatrix} = (-11 - \lambda)(12 - \lambda) - (11)(3) = \lambda^2 + 11\lambda - 132 - 33 = \lambda^2 + 11\lambda - 165 \]

\[ \begin{vmatrix}
-4 & 11 \\
5 & 12 - \lambda
\end{vmatrix} = (-4)(12 - \lambda) - (11)(5) = -48 + 4\lambda - 55 = 4\lambda - 103 \]

\[ \begin{vmatrix}
-4 & -11 - \lambda \\
5 & 3
\end{vmatrix} = (-4)(3) - (5)(-11 - \lambda) = -12 + 55 + 5\lambda = 43 + 5\lambda \]

Substituting these back into the determinant expression:
\[ \text{det}(A - \lambda I) = (-9 - \lambda)(\lambda^2 + 11\lambda - 165) + 5(4\lambda - 103) + 7(43 + 5\lambda) \]

Expanding each term:
\[ (-9 - \lambda)(\lambda^2 + 11\lambda - 165) = -9\lambda^2 - 99\lambda + 1485 - \lambda^3 - 11\lambda^2 + 165\lambda \]
\[ = -\lambda^3 - 20\lambda^2 + 66\lambda + 1485 \]

\[ 5(4\lambda - 103) = 20\lambda - 515 \]

\[ 7(43 + 5\lambda) = 301 + 35\lambda \]

Combining all terms:
\[ \text{det}(A - \lambda I) = -\lambda^3 - 20\lambda^2 + 66\lambda + 1485 + 20\lambda - 515 + 301 + 35\lambda \]
\[ = -\lambda^3 - 20\lambda^2 + (66\lambda + 20\lambda + 35\lambda) + (1485 - 515 + 301) \]
\[ = -\lambda^3 - 20\lambda^2 + 121\lambda + 1271 \]

Thus, the characteristic polynomial of the matrix is:
\[ \boxed{-\lambda^3 - 20\lambda^2 + 121\lambda + 1271} \]
-\lambda ^3-8 \lambda ^2+229 \lambda +1271
deepseek-v3 Error code: 400 - {'error': {'code': 'RequestTimeOut', 'param': None, 'message': 'Request timed out, please try again later.', 'type': 'RequestTimeOut'}, 'id': 'chatcmpl-91ca6ec4-9fe1-9a71-8d55-b6313d1cc3d2', 'request_id': '91ca6ec4-9fe1-9a71-8d55-b6313d1cc3d2'} -\lambda ^3-8 \lambda ^2+229 \lambda +1271