Table of contents
- 0. Review of Algebra4h 16m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 6m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 19m
- 10. Combinatorics & Probability1h 45m
6. Exponential & Logarithmic Functions
Introduction to Logarithms
Problem 59b
Textbook Question
Graph each function. Give the domain and range. ƒ(x) = (log↓2 x) + 3
![](/channels/images/assetPage/verifiedSolution.png)
1
Step 1: Understand the basic form of the function. The function \( f(x) = \log_2(x) + 3 \) is a logarithmic function with a vertical shift.
Step 2: Identify the domain of the function. Since \( \log_2(x) \) is only defined for \( x > 0 \), the domain of \( f(x) \) is \( (0, \infty) \).
Step 3: Determine the range of the function. The range of a logarithmic function is all real numbers, so the range of \( f(x) \) is \( (-\infty, \infty) \).
Step 4: Consider the vertical shift. The function \( \log_2(x) \) is shifted up by 3 units, which affects the graph but not the domain or range.
Step 5: Sketch the graph. Start with the basic graph of \( \log_2(x) \), then shift the entire graph up by 3 units to represent \( f(x) = \log_2(x) + 3 \).
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Logarithmic Functions
Logarithmic functions, such as f(x) = log₂(x), are the inverses of exponential functions. They are defined for positive real numbers, meaning the input x must be greater than zero. The base of the logarithm indicates the number that is raised to a power to obtain x. Understanding the properties of logarithms is essential for analyzing their graphs and determining their domains and ranges.
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Domain and Range
The domain of a function refers to all possible input values (x-values) that the function can accept, while the range refers to all possible output values (f(x)-values) that the function can produce. For the function f(x) = log₂(x) + 3, the domain is x > 0, and the range is all real numbers greater than 3. Identifying the domain and range is crucial for graphing functions accurately.
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Domain & Range of Transformed Functions
Graphing Functions
Graphing functions involves plotting points on a coordinate plane to visualize the relationship between the input and output values. For f(x) = log₂(x) + 3, the graph will show a logarithmic curve that shifts upward by 3 units. Understanding how to graph functions helps in interpreting their behavior and characteristics, such as asymptotes and intercepts.
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