Let A = [1, -1, 2; 0, 2, -3; 3, -2, 4] and B =1/3 [-2, 0, 1; 9, 2, -3; 6, 1, λ]. If AB = I, then the value of λ is:

Let $\displaystyle \mathrm{A}=\left[\begin{array}{ccc}1 & -1 & 2 \\ 0 & 2 & -3 \\ 3 & -2 & 4\end{array}\right]$ and $\displaystyle \mathrm{B}=\frac{1}{3}\left[\begin{array}{ccc}-2 & 0 & 1 \\ 9 & 2 & -3 \\ 6 & 1 & \lambda\end{array}\right]$. If $\displaystyle \mathrm{AB}=\mathrm{I}$, then the value of $\displaystyle \lambda$ is :