8 6 Linear Exponential and Quadratic Functions What
- Slides: 7
8. 6 Linear, Exponential, and Quadratic Functions
What We Will Learn • Choose appropriate function • Story problems
Ex. 1 Using Graphs to Identify Functions • Core Concept:
Ex. 1 continued • Plot the points and tell what kind of function it is. • (4, 4), (2, 0), (0, 0), (1, -. 5), (-2, 4) • quadratic
Ex. 2 Identifying From a Table • Looking at y’s • Linear: first differences are constant by adding or subtracting • Exponential: y values are multiplying or dividing • Quadratic: second differences are constant by adding or subtracting • Linear X -3 -2 -1 0 1 Y 11 8 5 2 -1 -3 -3 First differences
Ex. 2 Continued X -2 -1 0 1 2 Y 1 2 4 8 16 Y -1 -2 -1 2 7 x 2 x 2 +1 -1 +2 • exponential • quadratic +5 +3 +2 +2 First differences Second differences
Ex. 5 Story Problems • In 1900, Littleton had a population of 1000 people. Littleton’s population increased by 50 people each year. In 1900, Tinyville had a population of 500 people. Tinyville’s population increased by 5% each year. • A. In what year were the populations about equal? • B. Suppose Littleton’s initial population was 2000 and maintained the constant rate of change. Did Tinyville still catch up to Littleton and in what year? • C. Did Tinyville still catch up to Littleton is start with 2000 people and changes by 100 people per year? • D. Why did Tinyville always catch up to Littleton?
