I should check if there are any well-known textbooks or courses that refer to "azimuts 3a." Alternatively, maybe it's a French term since "azimut" is written differently in some languages. In French, "azimut" is spelled the same as in English. If that's the case, perhaps the user is a non-native English speaker who might have made a spelling mistake. They might be referring to a specific chapter or section in a French math textbook, possibly involving azimuths in coordinate geometry.
