68 STEP 4. Review the Knowledge You Need to Score High
- Evaluate limx→ 5 −
x^2
x^2 − 25
.
Answer: The limit is−∞, since (x^2 −25) approaches 0 through negative values.- Find the vertical and horizontal asymptotes of f(x)=
1
x^2 − 25.
Answer: The vertical asymptotes arex=±5, and the horizontal asymptote isy=0,
since limx→±∞f(x)=0.