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
4. Applications of Derivatives
Motion Analysis
Problem 18b
Textbook Question
Position, velocity, and acceleration Suppose the position of an object moving horizontally along a line after t seconds is given by the following functions s = f(t), where s is measured in feet, with s > 0 corresponding to positions right of the origin.
b. Find and graph the velocity function. When is the object stationary, moving to the right, and moving to the left?
f(t) = 18t-3t²; 0 ≤ t ≤ 8
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1
Step 1: Understand the relationship between position, velocity, and acceleration. The position function s = f(t) describes the location of an object at time t. The velocity function v(t) is the derivative of the position function, representing the rate of change of position with respect to time.
Step 2: Differentiate the position function f(t) = 18t - 3t^2 to find the velocity function v(t). Use the power rule for differentiation: if f(t) = at^n, then f'(t) = n*at^(n-1).
Step 3: Apply the power rule to each term in f(t). The derivative of 18t is 18, and the derivative of -3t^2 is -6t. Therefore, the velocity function is v(t) = 18 - 6t.
Step 4: Determine when the object is stationary by setting the velocity function equal to zero and solving for t. This will give the time(s) when the object is not moving.
Step 5: Analyze the sign of the velocity function to determine when the object is moving to the right (v(t) > 0) and moving to the left (v(t) < 0). This involves solving inequalities based on the velocity function.
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