JEE Math Practice Question
If $$A = \left[ {\begin{matrix} 1 & 2 & 2 \\ 2 & 1 & { - 2} \\ a & 2 & b \\ \end{matrix} } \right]$$ is a matrix satisfying the equation $$A{A^T} = 9\text{I},$$ where $$I$$ is $$3 \times 3$$ identity matrix, then the ordered pair $$(a, b)$$ is equal to :
- A.$$(2, 1)$$
- B.$$(-2, -1)$$
- C.$$(2, -1)$$
- D.$$(-2, 1)$$
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