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 3.2.11
Textbook Question
Use limits to find f' (x) if f(x) = 7x.
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1
Step 1: Recall the definition of the derivative using limits. The derivative of a function f(x) at a point x is given by the limit: f'(x) = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h}.
Step 2: Substitute the given function f(x) = 7x into the derivative definition. This gives us: f'(x) = \lim_{h \to 0} \frac{7(x+h) - 7x}{h}.
Step 3: Simplify the expression inside the limit. Distribute the 7 in the numerator: 7(x+h) = 7x + 7h. So, the expression becomes: \frac{7x + 7h - 7x}{h}.
Step 4: Cancel out the terms in the numerator. The 7x terms cancel each other, leaving: \frac{7h}{h}.
Step 5: Simplify the fraction by canceling h in the numerator and denominator, resulting in 7. Therefore, f'(x) = \lim_{h \to 0} 7 = 7.
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