If $A=\left[\begin{array}{ccc}1 & 2 & 2 \ 2 & 1 & -2 \ a & 2 & b\end{array} ight]$ is a matrix satisfying the equation $A A^T=9 I$ where $I$ is the identity matrix, then $a^2+b^2=$

Question

If $A=\left[\begin{array}{ccc}1 & 2 & 2 \ 2 & 1 & -2 \ a & 2 & b\end{array}ight]$ is a matrix satisfying the equation $A A^T=9 I$ where $I$ is the identity matrix, then $a^2+b^2=$

Aicharya · Accepted Answer

No solution. Refer to answer key.

If $A=\left[\begin{array}{ccc}1 & 2 & 2 \\ 2 & 1 & -2 \\ a & 2 & b\end{array}\right]$ is a matrix satisfying…

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