A simple solution is to do separate lists, the last two ones starting at indices different from 1. 
If you need help in setting up the initial counter for the list, send me your best guess privately and I will do my best to help. 

An alternative approach is to revert to the standard margins temporarily from within the list. This is actually a cleaner solution, albeit a little more difficult one to set up. 

hi

i have such a list (picture) :

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both sentences "On pose désormais..." and "Soit C'(O',r') un autre cercle..." would, in my opinion, be better if no indented, at the same level than the beginning (firts sentence) : "C cercle de centre O et de rayon..."

How can i "surf" outside and inside the list, being left-aligned on the left margin for general text, and 1 tab aligned for numeroted questions ?

Vincent

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Vincent Douce Mathoscope

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