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If A=[2312],I=[1001]A=\begin{bmatrix}2 & 3\\1 & 2\end{bmatrix}, I=\begin{bmatrix}1 & 0\\0 & 1\end{bmatrix} and A2=αA+βIA^2=\alpha A+\beta I, for some constant α\alpha and β\beta then the value of α\alpha and β\beta respectively:

Solution

✅ Correct Option: 4

A2=[71247]A^2=\begin{bmatrix}7&12\\4&7\end{bmatrix} and αA+βI=[2α+β3αα2α+β]\alpha A+\beta I=\begin{bmatrix}2\alpha+\beta&3\alpha\\\alpha&2\alpha+\beta\end{bmatrix}. Comparing, 3α=123\alpha=12 gives α=4\alpha=4, and 2(4)+β=72(4)+\beta=7 gives β=−1\beta=-1.

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