Falling meteorite The velocity of a heavy meteorite entering Earth’s atmosphere is inversely proportional to √s when it is s km from Earth’s center. Show that the meteorite’s acceleration is inversely proportional to s².
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 3h 16m
- 11. Integrals of Inverse, Exponential, & Logarithmic Functions2h 34m
- 12. Techniques of Integration7h 41m
- 13. Intro to Differential Equations2h 55m
- 14. Sequences & Series5h 36m
- 15. Power Series2h 19m
- 16. Parametric Equations & Polar Coordinates7h 58m
3. Techniques of Differentiation
The Chain Rule
Problem 3.6.6
Textbook Question
Derivative Calculations
In Exercises 1–8, given y = f(u) and u = g(x), find dy/dx = f'(g(x)) g'(x).
y = sin u, u = x − cos x

1
First, identify the functions involved: y = sin(u) and u = x - cos(x). We need to find dy/dx using the chain rule.
Apply the chain rule: dy/dx = (dy/du) * (du/dx). This means we need to find the derivative of y with respect to u and the derivative of u with respect to x.
Calculate dy/du: Since y = sin(u), the derivative dy/du is cos(u).
Calculate du/dx: For u = x - cos(x), the derivative du/dx is 1 + sin(x), because the derivative of x is 1 and the derivative of -cos(x) is sin(x).
Combine the derivatives using the chain rule: dy/dx = cos(u) * (1 + sin(x)). Substitute u = x - cos(x) into the expression to get dy/dx = cos(x - cos(x)) * (1 + sin(x)).

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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Chain Rule
The chain rule is a fundamental differentiation technique used when dealing with composite functions. It states that the derivative of a composite function y = f(g(x)) is found by multiplying the derivative of the outer function f with respect to its inner function g, by the derivative of the inner function g with respect to x. This is essential for calculating dy/dx when y and u are functions of x.
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Derivative of Trigonometric Functions
Understanding the derivatives of trigonometric functions is crucial for solving problems involving these functions. For instance, the derivative of sin(u) with respect to u is cos(u). This knowledge is necessary to apply the chain rule effectively when differentiating y = sin(u) in terms of x, where u is a function of x.
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Differentiation of Composite Functions
Differentiation of composite functions involves applying the chain rule to find the derivative of a function that is composed of other functions. In the given problem, y = sin(u) and u = x - cos(x) are composite functions, requiring the application of the chain rule to find dy/dx by differentiating each component function separately and then combining the results.
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