[tex](adsbygoogle = window.adsbygoogle || []).push({});

c = \left[ {\begin{array}{*{20}c}

{2 - x} & 5 & 1 \\

{ - 3} & 0 & x \\

{ - 2} & 1 & 2 \\

\end{array}} \right][/tex]

a) Calculate det(C).

My answer was [tex]x^2 - 12x + 27[/tex].

b) Calculate det(2C).

Umm, would this just be 2*det(C)?

Couldn't find anything more helpful in my notes.

c) State the values for 'x' for which C is not invertible.

I believe the value for 'x' that would make this non invertable would be the solution that det(c) = 0. (A matrix has no inverse when the determinant = 0 yeh?)

which would be x = 9 or 3

is this correct?

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# Matrix/Determinant/Inverse Q's

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