7.2 CHAPTER 7. DIFFERENTIAL CALCULUS
x
y
7 − 5 − − 3 − (^11357)
1
3
− 1
− 3
Figure 7.2: Graph of y =^1 x.
As x→ 0 from the left, y =^1 xapproaches−∞. As x→ 0 from the right, y =^1 xapproaches +∞. This
is written in limits notation as:
lim
x→ 0 −
1
x
=−∞
for x approaching 0 from the left and
lim
x→ 0 +
1
x
=∞
for x approaching 0 from the right. You cancalculate the limit of many different functions using a set
method.
Method:
Limits: If you are required to calculate a limit like limx→athen:
- Simplify the expression completely.
- If it is possible, cancel all common terms.
- Let x approach a.
Example 2: Limits
QUESTION
Determine
lim
x→ 1