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
5. Graphical Applications of Derivatives
Intro to Extrema
Problem 4.1.89a
Textbook Question
Values of related functions Suppose f is differentiable on (-∞,∞) and assume it has a local extreme value at the point x = 2, where f(2) = 0. Let g(x) = xf(x) + 1 and let h(x) = xf(x) + x +1, for all values of x.
a. Evaluate g(2), h(2), g'(2), and h'(2).
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1
First, evaluate g(2) by substituting x = 2 into the function g(x) = xf(x) + 1. This gives g(2) = 2f(2) + 1.
Since f(2) = 0, simplify g(2) to find its value.
Next, evaluate h(2) by substituting x = 2 into the function h(x) = xf(x) + x + 1. This gives h(2) = 2f(2) + 2 + 1.
Again, use the fact that f(2) = 0 to simplify h(2) and find its value.
To find g'(2) and h'(2), apply the product rule and the sum rule of differentiation to g(x) and h(x) respectively, then substitute x = 2 into the derivatives.
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