Source: https://www.axelnax.fr/contenu/04.%20Premi%C3%A8re%20technologique%20(S%C3%A9rie%20STL%20et%20STI2D)/01.%20Math%C3%A9matiques/03.%20Activit%C3%A9s/02.%20G%C3%A9n%C3%A9ralit%C3%A9s%20sur%20les%20fonctions/G%C3%A9n%C3%A9ralit%C3%A9s_sur_les_fonctions.pdf