https://es.symbolab.com/solver/limit-calculator/%5Clim_%7Bx%5Cto%203%7D%5Cleft(%5Cfrac%7Bx%5E%7B2%7D-9%7D%7Bx-3%7D%5Cright)
REPASO DERIVADAS https://www.examtime.com/es/p/957561