- #1
Jhenrique
- 685
- 4
Given the following: $$\\ \begin{bmatrix}
A & 0\\
0 & B\\
\end{bmatrix}$$ the eigenvalues is exactaly A and B. So analogously, is possible to write a matrix with only two elements, T and D, such that the trace is T and the determinant is D?
I tried something: $$\\ \text{tr} \left(
\begin{bmatrix}
\frac{1}{2}T & 0\\
0 & \frac{1}{2}T\\
\end{bmatrix}
\right) = T $$
$$\\ \text{det} \left(
\begin{bmatrix}
\sqrt{\frac{D}{2}} & \sqrt{-\frac{D}{2}} \\
\sqrt{-\frac{D}{2}} & \sqrt{\frac{D}{2}} \\
\end{bmatrix}
\right) = D $$
But I can't join the 2 formulas...
A & 0\\
0 & B\\
\end{bmatrix}$$ the eigenvalues is exactaly A and B. So analogously, is possible to write a matrix with only two elements, T and D, such that the trace is T and the determinant is D?
I tried something: $$\\ \text{tr} \left(
\begin{bmatrix}
\frac{1}{2}T & 0\\
0 & \frac{1}{2}T\\
\end{bmatrix}
\right) = T $$
$$\\ \text{det} \left(
\begin{bmatrix}
\sqrt{\frac{D}{2}} & \sqrt{-\frac{D}{2}} \\
\sqrt{-\frac{D}{2}} & \sqrt{\frac{D}{2}} \\
\end{bmatrix}
\right) = D $$
But I can't join the 2 formulas...