In 1770 he also presented his important work Réflexions sur la résolution algébrique des équations which made a fundamental investigation of why equations of degrees up to 4 could be solved by radicals .
Sa 1770 siya rin ipinapahayag ang kanyang mahalagang trabaho Réflexions sur la resolution algébrique des equation na ginawa ng isang pangunahing mga pagsisiyasat ng kung bakit equation ng mga degree ng hanggang 4 na maaaring malulutas sa pamamagitan ng radicals.