Math Problem Statement

Which of the following are true statements about limits? Mark all that are true.

Solution

The problem you uploaded involves evaluating several statements about limits. Let's break down each option and determine which ones are true based on the properties of limits.

Given:

We have several statements involving the limit of a function f(x)f(x) as xx approaches aa from the left and right.

  1. First statement:
    limxa+f(x)=8andlimxaf(x)=8implies thatlimxaf(x)=8\lim_{x \to a^+} f(x) = 8 \quad \text{and} \quad \lim_{x \to a^-} f(x) = 8 \quad \text{implies that} \quad \lim_{x \to a} f(x) = 8
    This is true. If the one-sided limits (from the left and from the right) are both equal to 8, then the two-sided limit exists and is also equal to 8.

  2. Second statement:
    limxa+f(x)=8implies thatlimxaf(x)=8\lim_{x \to a^+} f(x) = 8 \quad \text{implies that} \quad \lim_{x \to a} f(x) = 8
    This is false. The limit from the right does not necessarily imply the two-sided limit. We need both one-sided limits to be equal to 8 for the two-sided limit to exist and be 8.

  3. Third statement:
    limxaf(x)=8implies thatlimxa+f(x)=8\lim_{x \to a} f(x) = 8 \quad \text{implies that} \quad \lim_{x \to a^+} f(x) = 8
    This is false. If the two-sided limit exists, we know the limits from both sides must exist and be equal. However, a single-sided limit cannot be inferred from the two-sided limit unless both are considered.

  4. Fourth statement:
    limxaf(x)=8andlimxaf(x)=8implies thatlimxa+f(x)=8\lim_{x \to a} f(x) = 8 \quad \text{and} \quad \lim_{x \to a^-} f(x) = 8 \quad \text{implies that} \quad \lim_{x \to a^+} f(x) = 8
    This is true. If the two-sided limit and the left-hand limit are both 8, the right-hand limit must also be 8 for the two-sided limit to exist.

  5. Fifth statement:
    limxaf(x)=8implies thatlimxaf(x)=8\lim_{x \to a^-} f(x) = 8 \quad \text{implies that} \quad \lim_{x \to a} f(x) = 8
    This is false. The left-hand limit does not necessarily imply the two-sided limit. Both one-sided limits must be the same for the two-sided limit to exist.

  6. Sixth statement:
    limxaf(x)=8implies thatlimxaf(x)=8\lim_{x \to a} f(x) = 8 \quad \text{implies that} \quad \lim_{x \to a^-} f(x) = 8
    This is true. If the two-sided limit is 8, both the left-hand and right-hand limits must also be 8.

Summary of correct answers:

  • True: First, Fourth, Sixth
  • False: Second, Third, Fifth

Let me know if you need any further clarification or additional details about limits!


Related questions:

  1. What is the definition of the two-sided limit?
  2. How do we determine if the limit of a function at a point exists?
  3. What does it mean for the left-hand limit to equal the right-hand limit?
  4. How can a discontinuity in a function affect its limits?
  5. How do we approach limits involving infinite values?

Tip: Always check if the left-hand and right-hand limits are equal before concluding that the two-sided limit exists.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Limits
One-sided limits
Two-sided limits
Continuity

Formulas

lim_{x → a} f(x) exists if and only if lim_{x → a^+} f(x) = lim_{x → a^-} f(x)
If lim_{x → a} f(x) = L, then lim_{x → a^+} f(x) = L and lim_{x → a^-} f(x) = L

Theorems

Limit Existence Theorem
Properties of One-sided and Two-sided Limits

Suitable Grade Level

College Calculus or Advanced High School Calculus