Ako zistíte limit lim_ (x -> - 4) (x ^ 2 + 5x + 4) / (x ^ 2 + 3x-4)?

Ako zistíte limit lim_ (x -> - 4) (x ^ 2 + 5x + 4) / (x ^ 2 + 3x-4)?
Anonim

#=3/5#

vysvetlenie, Použitie vyhľadávacích limitov algebraicky, # = Lim_ (x -> - 4) (x ^ 2 + 5x + 4) / (x ^ 2 + 3-4) #, ak zapojíme # X = -4 #, dostaneme #0/0# formulár

# = Lim_ (x -> - 4) (x ^ 2 + 4x + x + 4) / (x ^ 2 + 4x-x-4) #

# = Lim_ (x -> - 4) (x (x + 4) 1 (x + 4)) / (x (x + 4) -1 (x + 4)) #

# = Lim_ (x -> - 4) ((x + 4) (x + 1)) / ((x + 4) (x-1)) #

# = Lim_ (x -> - 4) ((x + 1)) / ((x-1)) #

#=(-3)/-5#

#=3/5#