Document Type : Research Paper


Department of Mathematics, Faculty of Science, Arak University, Arak 38156-8-8349, Arak, Iran.


In this paper, we first give a description of a surjective unit-preserving real-linear uniform isometry $ T : A \longrightarrow B$,  where $ A $ and $ B $ are complex function spaces on compact Hausdorff spaces $ X $ and $ Y $, respectively, whenever ${\rm ER}\left (A, X\right ) = {\rm Ch}\left (A, X\right )$ and ${\rm ER}\left (B, Y\right ) = {\rm Ch}\left (B, Y\right )$. Next, we give a description of $ T $ whenever $ A $ and $ B $ are complex function algebras  and $ T $ does not assume to be unit-preserving.


Main Subjects

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