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
- 8. Definite Integrals4h 44m
- 9. Graphical Applications of Integrals2h 27m
- 10. Physics Applications of Integrals 2h 22m
1. Limits and Continuity
Finding Limits Algebraically
Problem 59
Textbook Question
Evaluate each limit.
lim x→0 e^4x−1 / e^x−1

1
Step 1: Recognize that the limit is in an indeterminate form 0/0 as x approaches 0. This suggests that L'Hôpital's Rule might be applicable.
Step 2: Apply L'Hôpital's Rule, which states that if the limit of f(x)/g(x) as x approaches a point results in an indeterminate form, then the limit can be found by taking the derivative of the numerator and the derivative of the denominator separately.
Step 3: Differentiate the numerator e^{4x} - 1 with respect to x. The derivative of e^{4x} is 4e^{4x}, and the derivative of -1 is 0.
Step 4: Differentiate the denominator e^x - 1 with respect to x. The derivative of e^x is e^x, and the derivative of -1 is 0.
Step 5: Substitute the derivatives back into the limit expression and evaluate the new limit: lim x→0 (4e^{4x}) / (e^x). Simplify the expression and evaluate the limit as x approaches 0.

This video solution was recommended by our tutors as helpful for the problem above
Video duration:
3mPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Limits
A limit is a fundamental concept in calculus that describes the behavior of a function as its input approaches a certain value. In this case, we are interested in the limit of the function as x approaches 0. Understanding limits is crucial for evaluating functions that may not be directly computable at specific points, especially when they lead to indeterminate forms.
Recommended video:
One-Sided Limits
Exponential Functions
Exponential functions are mathematical functions of the form f(x) = e^(kx), where e is the base of the natural logarithm and k is a constant. These functions are characterized by their rapid growth and unique properties, such as the fact that the derivative of e^x is e^x. In the limit problem, we are dealing with the exponential functions e^(4x) and e^x, which will influence the behavior of the limit as x approaches 0.
Recommended video:
Exponential Functions
L'Hôpital's Rule
L'Hôpital's Rule is a method used to evaluate limits that result in indeterminate forms like 0/0 or ∞/∞. It states that if the limit of f(x)/g(x) leads to such a form, the limit can be found by taking the derivative of the numerator and the derivative of the denominator separately. This rule is particularly useful in the given limit problem, as both the numerator and denominator approach 0 as x approaches 0.
Recommended video:
Guided course
Power Rules
Watch next
Master Finding Limits by Direct Substitution with a bite sized video explanation from Callie
Start learningRelated Videos
Related Practice