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
Tangent Lines and Derivatives
Problem 7
Textbook Question
An equation of the line tangent to the graph of f at the point (2,7) is y = 4x−1. Find f(2) and f′(2).
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1
Step 1: Understand that the equation of the tangent line at a point (a, f(a)) on the graph of a function f is given by y = f'(a)(x - a) + f(a).
Step 2: Recognize that the given tangent line equation is y = 4x - 1, which can be compared to the general form y = mx + b, where m is the slope of the tangent line.
Step 3: Identify that the slope of the tangent line, m, is 4. This means that f'(2) = 4, as the slope of the tangent line at x = 2 is the derivative of the function at that point.
Step 4: Use the point (2, 7) given in the problem, which lies on both the function f and the tangent line, to find f(2). Since the point is on the tangent line, substitute x = 2 into the tangent line equation: y = 4(2) - 1.
Step 5: Conclude that f(2) = 7, as the y-coordinate of the point (2, 7) is the value of the function at x = 2.
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