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
2. Intro to Derivatives
Derivatives as Functions
Problem 3.1.56
Textbook Question
Find the function The following limits represent the slope of a curve y = f(x) at the point (a,f(a)). Determine a possible function f and number a; then calculate the limit.
(lim x🠂1) 3x²+4x-7 / x-1
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1
Step 1: Recognize that the given limit represents the derivative of a function f(x) at a point x = a. The expression (lim x→1) (3x² + 4x - 7) / (x - 1) suggests that we are dealing with a derivative at x = 1.
Step 2: Identify the form of the limit. The expression (3x² + 4x - 7) / (x - 1) is in the form of a difference quotient, which is typically used to find the derivative of a function at a specific point.
Step 3: Assume that the function f(x) is a polynomial, since the numerator is a polynomial. A reasonable assumption is that f(x) = 3x² + 4x - 7, which is a quadratic function.
Step 4: To find the derivative f'(x), apply the power rule to each term of the polynomial: f'(x) = d/dx [3x²] + d/dx [4x] - d/dx [7].
Step 5: Evaluate the derivative at x = 1 to find the slope of the tangent line at that point. Substitute x = 1 into f'(x) to calculate the limit.
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