3: Limit at −∞:

Horizontal asymptote y = 3 at −∞.

Limit at x = 0 from the left:

No vertical asymptote at x = 0 yet.

Limit at x = 0 from the right:

Vertical asymptote at x = 0.

Limit at ∞:

Horizontal asymptote y = 3 at ∞.

Answer