[racket] Completion of Tex keybindings on apple keyboard

Hi,

I use an apple machine, i cannot succed to produce some key sequences.

I want to use tex symbols in my code as \diamond...  A sequence of special keys is given to produce the respective printing of tex caracters :
C-\ M-\
should produce a backward completion backto the antislash and should replace it by a real diamond but it does not work.

The racket editor indicates 
~:m:c:\   it does nots work al well (difficult to do : crtl+alt+cmd+N+/  !!!)

Thanks for advices, Respectuously 

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David Delfieu, tel : 02 40 90 50 45			
EC à Polytech'Nantes - Département Génie Électrique 
Site de Gavy, 44603 Saint Nazaire Cedex		
Chercheur à L'IRCCyN						
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