An eigen vector of \[{\text{P}} = \left[ {\begin{array}{*{20}{c}} 1&1&0 \\ 0&2&2 \\ 0&0&3 \end{array}} \right]\] is A. [-1 1 1]T B. [1 2 1]T C. [1 -1 2]T D. [2 1 -1]T

”[-1
T” option2=”[1 2 1]T” option3=”[1 -1 2]T” option4=”[2 1 -1]T” correct=”option1″]

The correct answer is $\boxed{\text{(C)}}$.

An eigenvector of a matrix $A$ is a vector $v$ such that $Av = \lambda v$ for some scalar $\lambda$. In other words, an eigenvector is a vector that is scaled by a constant when it is multiplied by the matrix.

To find the eigenvectors of a matrix, we can use the following formula:

$$v = \left[ {\begin{array}{*{20}{c}} x_1 \\ x_2 \\ x_3 \end{array}} \right]$$

$$Av = \left[ {\begin{array}{*{20}{c}} a_{11}x_1 + a_{12}x_2 + a_{13}x_3 \\ a_{21}x_1 + a_{22}x_2 + a_{23}x_3 \\ a_{31}x_1 + a_{32}x_2 + a_{33}x_3 \end{array}} \right]$$

$$\lambda v = \left[ {\begin{array}{*{20}{c}} \lambda x_1 \\ \lambda x_2 \\ \lambda x_3 \end{array}} \right]$$

$$\left[ {\begin{array}{{20}{c}} a_{11} – \lambda & a_{12} & a_{13} \\ a_{21} & a_{22} – \lambda & a_{23} \\ a_{31} & a_{32} & a_{33} – \lambda \end{array}} \right] \left[ {\begin{array}{{20}{c}} x_1 \\ x_2 \\ x_3 \end{array}} \right] = 0$$

To find the eigenvalues, we can solve the equation $|A – \lambda I| = 0$.

In this case, we have:

$$|A – \lambda I| = \left| \begin{array}{ccc} 1 & 1 & 0 \\ 0 & 2 & 2 \\ 0 & 0 & 3 – \lambda \end{array} \right| = \lambda^3 – 6 \lambda^2 + 11 \lambda – 6$$

We can factor this equation as follows:

$$\lambda^3 – 6 \lambda^2 + 11 \lambda – 6 = (\lambda – 2)(\lambda – 3)(\lambda – 2)$$

Therefore, the eigenvalues of $A$ are $\lambda = 2$, $\lambda = 3$, and $\lambda = 2$.

To find the eigenvectors corresponding to each eigenvalue, we can substitute each eigenvalue into the equation $|A – \lambda I| = 0$ and solve for $x_1$, $x_2$, and $x_3$.

For $\lambda = 2$, we have:

$$\left| \begin{array}{ccc} 2 – 2 & 1 & 0 \\ 0 & 2 – 2 & 2 \\ 0 & 0 & 3 – 2 \end{array} \right| = \left| \begin{array}{ccc} 0 & 1 & 0 \\ 0 & 0 & 2 \\ 0 & 0 & 1 \end{array} \right| = 0$$

Therefore, the eigenvector corresponding to $\lambda = 2$ is $v = [0 1 0]^T$.

For $\lambda = 3$, we have:

$$\left| \begin{array}{ccc} 3 – 3 & 1 & 0 \\ 0 & 3 – 3 & 2 \\ 0 & 0 & 3 – 3 \end{array} \right| = \left| \begin{array}{ccc} 0 & 1 & 0 \\ 0 & 0 & 0 \\ 0 & 0 & 0 \end{array} \right| = 0$$

Therefore, the eigenvector corresponding to $\lambda = 3$ is $v = [0 0 1]^T$.

For $\lambda = 2$, we have:

$$\left| \begin{array}{ccc} 2 – 2 & 1 &

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