Respuesta :

maximum point: (–2.4, 37.014) and minimum point: (2.4, –37.014) 

maximum point: (2.4, –37.014) and minimum point: (–2.4, 37.014) 

maximum point: (–1.4, 33.014) and minimum point: (1.4, –33.014) 

maximum point: (–3, 30) and minimum point: (3, –30)