Math Problem Statement

The graph of the function f is shown in the figure. Which of the following statements about f is true?

Solution

Let's analyze the graph and the question to determine which of the given statements is true.

Step 1: Examine the graph

In the graph, we see two key points labeled aa and bb on the x-axis:

  • At x=ax = a, there is a discontinuity. The graph approaches different values from the left and right.
  • At x=bx = b, the function seems continuous and has a defined value.

Step 2: Analyze limits based on the graph

For x=ax = a:

  • The left-hand limit as xax \to a^- seems to approach 3.
  • The right-hand limit as xa+x \to a^+ seems to approach 1.
  • Since the left-hand limit and right-hand limit are not equal, the limit as xax \to a does not exist.

For x=bx = b:

  • The graph is continuous at x=bx = b.
  • The value of the function f(b)f(b) appears to be 1-1.
  • The limit as xbx \to b is 1-1, which is also the value of the function at x=bx = b.

Step 3: Evaluate the statements

Now we can check the statements:

A) limxaf(x)=limxbf(x)\lim_{x \to a} f(x) = \lim_{x \to b} f(x): This is false because the limit as xax \to a does not exist.

B) limxaf(x)=3\lim_{x \to a} f(x) = 3: This is false because the limit as xax \to a does not exist (the left-hand and right-hand limits are different).

C) limxbf(x)=3\lim_{x \to b} f(x) = 3: This is false because the limit as xbx \to b is 1-1, not 3.

D) limxbf(x)=1\lim_{x \to b} f(x) = -1: This is true since the limit as xbx \to b is 1-1.

E) limxaf(x)\lim_{x \to a} f(x) does not exist: This is true since the left-hand and right-hand limits as xax \to a are different.

Step 4: Conclusion

The correct answers are D and E.

Would you like further details on any part of the solution?


Here are some follow-up questions for you:

  1. What are the key conditions for the existence of a limit at a point?
  2. How would the graph change if the limit at x=ax = a existed?
  3. Can a function be discontinuous but still have a limit at a point?
  4. How does the graph of a function help in understanding one-sided limits?
  5. What are the implications of having equal left-hand and right-hand limits?

Tip: When evaluating limits from a graph, always check for one-sided limits to see if the limit exists at a given point.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Limits
Continuity
Graph Interpretation

Formulas

Limit definition
Left-hand and right-hand limits

Theorems

Existence of a limit
One-sided limits and discontinuities

Suitable Grade Level

Grades 10-12