Respuesta :

Lim [3 / (x^2 - 6x + 9)] = Lim [3 / (x -3)^2]    ...(by factoring)

Find the side limits:

x -->3 +    =>  Lim [3 / (x -3)^2] = 3/0 = ∞

x -->3 -    =>  Lim [3 / (x -3)^2] = 3/0 = ∞

Then the limit is ∞