Respuesta :

Answer:  The required matrix A is

[tex]A=\left[\begin{array}{ccc}4&5&2\\5&1&0\\2&0&3\end{array}\right] .[/tex]

Step-by-step explanation:  We are given to write a 3 × 3 symmetric matrix A that has entries as follows :

[tex]a_{11}=4,~~a_{22}=1,~~a_{33}=3,~~a_{21}=5,~~a_{13}=2,~~a_{23}=0.[/tex]

We know that in a symmetric matrix,

[tex]a_{ij}=a_{ji},~i\neq j.[/tex]

Since A is a 3 × 3 symmetric matrix, so we must have

[tex]a_{12}=a_{21}=5,\\\\a_{13}=a_{31}=2,\\\\a_{23}=a_{32}=0.[/tex]

Therefore, the 3 × 3 symmetric matrix A is written as follows :

[tex]A=\left[\begin{array}{ccc}4&5&2\\5&1&0\\2&0&3\end{array}\right] .[/tex]

Thus, the required matrix A is

[tex]A=\left[\begin{array}{ccc}4&5&2\\5&1&0\\2&0&3\end{array}\right] .[/tex]

Using the concept of symmetry, the matrix is given by:

[tex]M = \left[\begin{array}{ccc}4&5&2\\5&1&0\\2&0&3\end{array}\right][/tex]

A 3x3 matrix is given by:

[tex]M = \left[\begin{array}{ccc}a_{11}&a_{12}&a_{13}\\a_{21}&a_{22}&a_{32}\\a_{31}&a_{32}&a_{33}\end{array}\right][/tex]

The symmetry means that:

[tex]a_{ij} = a_{ji}[/tex]

Then:

[tex]a_{11} = 4[/tex]

[tex]a_{22} = 1[/tex]

[tex]a_{33} = 3[/tex]

[tex]a_{21} = a_{12} = 5[/tex]

[tex]a_{13} = a_{31} = 2[/tex]

[tex]a_{23} = a_{32} = 0[/tex]

Which means that the matrix is:

[tex]M = \left[\begin{array}{ccc}4&5&2\\5&1&0\\2&0&3\end{array}\right][/tex]

A similar problem is given at https://brainly.com/question/13266649

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