3.1 Day 2 Quadratic Functions and Models
November 07, 2008
3.1 Quadratic Functions and Models
Day 2
Objective:
Use the maximum or minimum value of a quadratic
function to solve applied problems
Nov 6­10:38 AM
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3.1 Day 2 Quadratic Functions and Models
November 07, 2008
Quadratic functions are used in many mathematical models:
Revenue function: maximum
Cost function: minimum
Nov 6­10:40 AM
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3.1 Day 2 Quadratic Functions and Models
November 07, 2008
Example #1:
The manufacturer of Knuckle Draggin' Snowboards found that when the unit price is p dollars, the revenue R (in dollars) is:
What is the unit price needed to maximize the revenue? What is the maximum revenue?
Nov 6­10:44 AM
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3.1 Day 2 Quadratic Functions and Models
November 07, 2008
Example #2: A farmer has 600 yards of fencing for a rectangular garden. Find the area of the garden as a function of the width x. What value of x will maximize the area? What is that area?
Nov 6­10:47 AM
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3.1 Day 2 Quadratic Functions and Models
November 07, 2008
Example #3: The height of a softball (in feet) hit by a batter is given by the equation: where x is the horizontal distance from the batter (in feet).
What is the horizontal distance from the batter when the ball is at its maximum height?
Find the maximum height of the softball. Nov 6­10:51 AM
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3.1 Day 2 Quadratic Functions and Models
November 07, 2008
Study example #12 on page 162
HW: p.165/72, 73, 79, 81, 86, 100
Nov 6­10:52 AM
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