# conjugate space

Find the coordinates

$\phi^\ast(\epsilon_{2}^\ast+\epsilon_{3}^\ast)$ in base $A^\ast$

where $A$ is $(3,4,5),(1,3,-2),(0,1,-2)$ and $M(\phi^\ast)_{st}^{st}=\begin{bmatrix} 1 & 3 & 2 \\ 2 & -4 & 1 \\ -3 & 1 & -1 \\ \end{bmatrix}$

Could someone explain the exercie for me?

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