Find x such that the matrix is equal to its own inverse.

$A=[3x,-2-3]$

Chaya Galloway
2021-02-25
Answered

Find x such that the matrix is equal to its own inverse.

$A=[3x,-2-3]$

You can still ask an expert for help

Usamah Prosser

Answered 2021-02-26
Author has **86** answers

When you multiply this matrix by itself, the first element is 9-2x that has to be equal to 1.

$9-2x=1$

$-2x=-8$

$x=4$

So the answer$x=4$ then the matrix is its own inverse!

$[[3,x],{[-2,-3]}^{2}=[[9-2x,3x-3x],[-6+6],[-2x+9]]]$

when$x=4$ then

$\left[\begin{array}{cc}1& 0\\ 0& 1\end{array}\right]$

Result:$x=4$

So the answer

when

Result:

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