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find all real numbers k for which there exists a nonzero 2 dimensional vector bold v such that begin bmatrix 2

User Chris VCB
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Answer:

We can write the given system of equations as a matrix equation:

$\begin{bmatrix} 2 & 4 \ 4 & k \end{bmatrix} \begin{bmatrix} x \ y \end{bmatrix} = \begin{bmatrix} 0 \ 0 \end{bmatrix}$

To find nontrivial solutions (i.e., $x$ and $y$ not both equal to zero), the coefficient matrix must be singular, which means its determinant must be zero:

$\det\begin{bmatrix} 2 & 4 \ 4 & k \end{bmatrix} = 2k - 16 = 2(k - 8) = 0$

Thus, $k = 8$ is the only value for which there exists a nonzero 2-dimensional vector $\boldsymbol{v} = \begin{bmatrix} x \ y \end{bmatrix}$ satisfying the given system of equations. For $k \\eq 8$, the only solution is the trivial one, $\boldsymbol{v} = \boldsymbol{0}$.


I hope this us helpful
User Donald
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