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 26b
Textbook Question
Determine the following limits.
b. lim x→−2^− (x − 4) / x(x + 2)
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1
Step 1: Identify the type of limit. Since the limit is as x approaches -2 from the left (x \to -2^-), we need to consider the behavior of the function as x gets closer to -2 from values less than -2.
Step 2: Analyze the function \( \frac{x - 4}{x(x + 2)} \). Notice that the denominator becomes zero when x = -2, which suggests a potential vertical asymptote at x = -2.
Step 3: Determine the sign of the function as x approaches -2 from the left. For x slightly less than -2, both x and (x + 2) are negative, making the denominator positive. The numerator (x - 4) is negative, resulting in the entire fraction being negative.
Step 4: Consider the magnitude of the function as x approaches -2 from the left. As x gets closer to -2, the denominator approaches zero, causing the magnitude of the fraction to increase without bound.
Step 5: Conclude the behavior of the limit. Since the function becomes increasingly negative as x approaches -2 from the left, the limit is negative infinity.
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