Table of contents
- 0. Functions7h 52m
- Introduction to Functions16m
- Piecewise Functions10m
- Properties of Functions9m
- Common Functions1h 8m
- Transformations5m
- Combining Functions27m
- Exponent rules32m
- Exponential Functions28m
- Logarithmic Functions24m
- Properties of Logarithms34m
- Exponential & Logarithmic Equations35m
- Introduction to Trigonometric Functions38m
- Graphs of Trigonometric Functions44m
- Trigonometric Identities47m
- Inverse Trigonometric Functions48m
- 1. Limits and Continuity2h 2m
- 2. Intro to Derivatives1h 33m
- 3. Techniques of Differentiation3h 18m
- 4. Applications of Derivatives2h 38m
- 5. Graphical Applications of Derivatives6h 2m
- 6. Derivatives of Inverse, Exponential, & Logarithmic Functions2h 37m
- 7. Antiderivatives & Indefinite Integrals1h 26m
1. Limits and Continuity
Finding Limits Algebraically
Problem 73c
Textbook Question
Let f(x) = {x^2+1 / if x<−1
√x+1 if x≥−1.
Compute the following limits or state that they do not exist.
limx→−1 f(x)
![](/channels/images/assetPage/verifiedSolution.png)
1
<insert step 1> Identify the piecewise function f(x) and the point of interest, which is x = -1. The function is defined as f(x) = x^2 + 1 for x < -1 and f(x) = \sqrt{x} + 1 for x \geq -1.
<insert step 2> To find the limit as x approaches -1, consider the left-hand limit (as x approaches -1 from the left) and the right-hand limit (as x approaches -1 from the right) separately.
<insert step 3> Calculate the left-hand limit: lim_{x \to -1^-} f(x) = lim_{x \to -1^-} (x^2 + 1). Substitute x = -1 into the expression x^2 + 1 to find the left-hand limit.
<insert step 4> Calculate the right-hand limit: lim_{x \to -1^+} f(x) = lim_{x \to -1^+} (\sqrt{x} + 1). Substitute x = -1 into the expression \sqrt{x} + 1 to find the right-hand limit.
<insert step 5> Compare the left-hand and right-hand limits. If they are equal, the limit exists and is equal to this common value. If they are not equal, the limit does not exist.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Piecewise Functions
A piecewise function is defined by different expressions based on the input value. In this case, f(x) has two distinct formulas: one for x < -1 and another for x ≥ -1. Understanding how to evaluate piecewise functions is crucial for determining limits at points where the function's definition changes.
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Piecewise Functions
Limits
A limit describes the behavior of a function as the input approaches a certain value. To compute the limit of f(x) as x approaches -1, we need to evaluate the function from both sides of -1, using the appropriate piece of the function for each side. This helps us determine if the limit exists and what its value is.
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One-Sided Limits
Left-Hand and Right-Hand Limits
Left-hand and right-hand limits refer to the values that a function approaches as the input approaches a specific point from the left or right, respectively. For the limit of f(x) as x approaches -1, we must calculate the left-hand limit (using x < -1) and the right-hand limit (using x ≥ -1) to see if they are equal, which would indicate the overall limit exists.
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One-Sided Limits
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