Pham TTC, Vo DT, Ngo TKY, Tran THY. The level-set method combined with Desmos software to orient the solution of inequality problems. Dong Thap University Journal of Science [Internet]. 2022 Feb. 14 [cited 2024 Sep. 8];11(1):3-11. Available from: https://dthujs.vn/index.php/dthujs/article/view/185