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 Integrals3h 25m
4. Applications of Derivatives
Motion Analysis
Problem 3.6.11c
Textbook Question
Highway travel A state patrol station is located on a straight north-south freeway. A patrol car leaves the station at 9:00 A.M. heading north with position function s = f(t) that gives its location in miles t hours after 9:00 A.M. (see figure). Assume s is positive when the car is north of the patrol station. <IMAGE>
c. Find the average velocity of the car over the interval [1.75, 2.25]. Estimate the velocity of the car at 11:00 A.M. and determine the direction in which the patrol car is moving.
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1
Identify the time interval for which you need to find the average velocity, which is from t = 1.75 hours to t = 2.25 hours after 9:00 A.M.
Use the position function s = f(t) to find the positions of the patrol car at the endpoints of the interval: calculate f(1.75) and f(2.25).
Apply the formula for average velocity over the interval [1.75, 2.25], which is given by the formula: average velocity = (f(2.25) - f(1.75)) / (2.25 - 1.75).
To estimate the velocity of the car at 11:00 A.M., which corresponds to t = 2 hours, evaluate the position function at that time: find f(2).
Determine the direction of the patrol car's movement by analyzing the sign of the velocity, which is the derivative of the position function, v(t) = f'(t). If v(t) > 0, the car is moving north; if v(t) < 0, it is moving south.
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