19: The condition x − 1 > 0 gives the domain
D( f ) = (−∞,1) ∪ (1,∞).
Now it is time to find limits at −∞, at 1 from the left and from the right, and at ∞.
Hint on limit at −∞ Hint on limit at 1 from the left Hint on limit at 1 from the right Hint on limit at ∞ Answer