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
4. Polynomial Functions
Quadratic Functions
Problem 7c
Textbook Question
Solve each problem. During the course of ayear, the number of volunteers available to run a food bank each month is modeled by V(x), where V(x)=2x^2-32x+150 between the months of January and August. Here x is time in months, with x=1 representing January. From August to December, V(x) is mod-eled by V(x)=31x-226. Find the number of volunteers in each of the following months. January

1
Identify the function that models the number of volunteers for January. Since January is between January and August, use the function V(x) = 2x^2 - 32x + 150.
Substitute x = 1 into the function V(x) = 2x^2 - 32x + 150 to find the number of volunteers in January.
Calculate the expression 2(1)^2 - 32(1) + 150.
Simplify the expression by performing the operations: first, calculate 2(1)^2, then subtract 32(1), and finally add 150.
The result of the simplified expression will give the number of volunteers in January.

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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Quadratic Functions
A quadratic function is a polynomial function of degree two, typically expressed in the form V(x) = ax^2 + bx + c. In this case, V(x) = 2x^2 - 32x + 150 represents the number of volunteers from January to August. Understanding how to evaluate quadratic functions is essential for determining the number of volunteers in specific months.
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Function Evaluation
Function evaluation involves substituting a specific input value into a function to find its output. For example, to find the number of volunteers in January, we substitute x = 1 into the quadratic function V(x). This process is crucial for solving the problem and obtaining the correct number of volunteers for each month.
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Piecewise Functions
A piecewise function is defined by different expressions based on the input value. In this scenario, V(x) is modeled by a quadratic function from January to August and a linear function from August to December. Recognizing how to work with piecewise functions is important for understanding the changes in the number of volunteers over the specified months.
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