Math Problem Statement

evaluate the given limits using the graph

Evaluate the limits for the function f(x) = 1 / (x + 1)^2 as x approaches -1 from both the left and right.

Solution

To evaluate the given limits, we are working with the function:

f(x)=1(x+1)2f(x) = \frac{1}{(x + 1)^2}

and need to analyze the following limits:

  • (a) limx1f(x)\lim_{x \to -1^-} f(x)
  • (b) limx1+f(x)\lim_{x \to -1^+} f(x)

Explanation of the limits:

  1. (a) Left-hand limit limx1f(x)\lim_{x \to -1^-} f(x):

    • This is the limit as xx approaches 1-1 from the left side.
    • As x1x \to -1^-, (x+1)0(x + 1) \to 0^-, meaning the term inside the parentheses approaches 00 from the negative side.
    • Since we are squaring (x+1)2(x+1)^2, this negative value becomes positive, and as (x+1)20+(x + 1)^2 \to 0^+, f(x)f(x) \to \infty.
    • Thus, limx1f(x)=\lim_{x \to -1^-} f(x) = \infty.
  2. (b) Right-hand limit limx1+f(x)\lim_{x \to -1^+} f(x):

    • This is the limit as xx approaches 1-1 from the right side.
    • As x1+x \to -1^+, (x+1)0+(x + 1) \to 0^+, meaning the term inside the parentheses approaches 00 from the positive side.
    • Again, squaring this term results in a positive value, and as (x+1)20+(x + 1)^2 \to 0^+, f(x)f(x) \to \infty.
    • Thus, limx1+f(x)=\lim_{x \to -1^+} f(x) = \infty.

Conclusion:

Both the left-hand and right-hand limits tend to infinity. Therefore:

  • limx1f(x)=\lim_{x \to -1^-} f(x) = \infty
  • limx1+f(x)=\lim_{x \to -1^+} f(x) = \infty

Let me know if you'd like more details, and here are some related questions to expand your understanding:

  1. What happens to the function as xx approaches 1-1 in general (without specifying direction)?
  2. How would the limits change if the function was 1(x+1)3\frac{1}{(x+1)^3}?
  3. What does it mean graphically when a function approaches infinity as xx approaches a certain value?
  4. Can we determine whether the function has any vertical asymptotes from the given limits?
  5. How do left-hand and right-hand limits relate to the concept of continuity?

Tip: When dealing with rational functions, it's often helpful to determine whether there's a vertical asymptote at certain points by checking where the denominator becomes zero.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Limits
Rational Functions
Asymptotes

Formulas

f(x) = 1 / (x + 1)^2

Theorems

Limit Theorem
Asymptote Theorem

Suitable Grade Level

Grades 10-12