Determiants

[spring stratus]

is there a smart way of doing this besides brute force?

An $n\times n$ matrix $C$ is type $I$ if $C^2=C$ and an $n\times n$ matrix $D$ is type $II$ if $D^2=0_{n}$. Determine if the following matrices are type $I, II,$ or neither: $$A=\begin{bmatrix}2&-2&-4\-1&3&4\1&-2&-3\end{bmatrix}, B=\begin{bmatrix}1&2&5\2&4&10\-1&-2&5\end{bmatrix}$$

[neon cave]

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[steel umbra]

Anonymous

[vague garnet]

Is matrix multiplication between a pair of 3x3 matrices really brute-force...

[spring stratus]

It probably ain’t but as someone who can’t use a calculator for this I feel like in def going to make a typo somewhere

Especially like it being an exam situation and if the following parts of the question depends on if u get this right or not

[thorn sinew]

I think it's intended to be resolved with brute force

So honestly just pray that you don't make mistakes

[spring stratus]

darn

[spring stratus]

alr cool noted, thank you