MathematicsHard244×since 2002Q4657If A = \left[ {\matrix{ 1 & 2 & 2 \cr 2 & 1 & { - 2} \cr a & 2 & b \cr } } \right] is a matrix satisfying the equation AAT=9I,A{A^T} = 9\text{I},AAT=9I, where III is 3×33 \times 33×3 identity matrix, then the ordered pair (a,b)(a, b)(a,b) is equal to :A(2,1)(2, 1)(2,1)B(−2,−1)(-2, -1)(−2,−1)C(2,−1)(2, -1)(2,−1)D(−2,1)(-2, 1)(−2,1)Check answerSkip