Talk:Antihomomorphism

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Another Basic Example

With matrices, another example of an antiautomorphism is given by the transpose map. Since inversion and transposing both give antiautomorphisms, their composition is an automorphism. This involution is often called the contragredient map, and it provides an example of an outer automorphism of the general linear group GL(n,F) where F is a field, except when |F|= 2 and n= 1 or 2 or |F| = 3 and n=1 (i.e., for the groups GL(1,2), GL(2,2), and GL(1,3)). —Preceding unsigned comment added by DavidLHarden (talkcontribs) 19:58, 7 August 2010 (UTC)[reply]