Given

\[A\text{ }=\text{ }diag\text{ }\left( 2\text{ }-5\text{ }9 \right),\text{ }\]

\[B\text{ }=\text{ }diag\text{ }\left( 1\text{ }1\text{ }-4 \right)\text{ }\]

\[and\text{ }C\text{ }=\text{ }diag\text{ }\left( -6\text{ }3\text{ }4 \right)\]

Now we have to find \[2A\text{ }+\text{ }3B\text{ }-\text{ }5C\]

Here,

Now consider \[2A\text{ }+\text{ }3B\text{ }-\text{ }5C\]