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 2h 22m
0. Functions
Combining Functions
Problem 1.1.70
Textbook Question
Simplify the difference quotient (ƒ(x)-ƒ(a)) / (x-a) for the following functions.
ƒ(x) = 4 - 4x + x²

1
Step 1: Start by substituting the function \( f(x) = 4 - 4x + x^2 \) into the difference quotient formula \( \frac{f(x) - f(a)}{x-a} \).
Step 2: Calculate \( f(a) \) by substituting \( a \) into the function: \( f(a) = 4 - 4a + a^2 \).
Step 3: Substitute \( f(x) \) and \( f(a) \) into the difference quotient: \( \frac{(4 - 4x + x^2) - (4 - 4a + a^2)}{x-a} \).
Step 4: Simplify the numerator by distributing and combining like terms: \( (4 - 4x + x^2) - (4 - 4a + a^2) = -4x + x^2 + 4a - a^2 \).
Step 5: Factor the simplified expression in the numerator, if possible, and then divide by \( x-a \) to simplify the difference quotient further.

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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Difference Quotient
The difference quotient is a formula used to calculate the average rate of change of a function over an interval. It is expressed as (ƒ(x) - ƒ(a)) / (x - a), where ƒ(x) is the function value at x and ƒ(a) is the function value at a. This concept is foundational in calculus as it leads to the definition of the derivative, which represents the instantaneous rate of change.
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Function Simplification
Function simplification involves rewriting a mathematical expression in a more manageable or understandable form. In the context of the given function ƒ(x) = 4 - 4x + x², simplification may include combining like terms, factoring, or expanding expressions. This process is crucial for effectively applying calculus concepts such as differentiation or integration.
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Properties of Functions
Calculus and Derivatives
Calculus is a branch of mathematics that studies continuous change, and derivatives are a key concept within it. The derivative of a function at a point provides the slope of the tangent line to the function at that point, representing the instantaneous rate of change. Understanding how to compute derivatives from the difference quotient is essential for analyzing the behavior of functions.
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Fundamental Theorem of Calculus Part 1
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