7­6 Day 2 Function Operatoins March 02, 2009
7­6 Day 2 Function Operations
Objective: Find the composite of two functions.
Feb 27­1:38 PM
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7­6 Day 2 Function Operatoins March 02, 2009
Check Skills You'll Need
Evaluate f(x) = 2x2 ­ 5 for the following:
1. f(2)
2. f(­1)
3. f(10)
4. f(x ­ 1)
Feb 27­1:38 PM
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7­6 Day 2 Function Operatoins March 02, 2009
Feb 27­1:38 PM
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7­6 Day 2 Function Operatoins March 02, 2009
Composition of Functions
Let f(x) = x ­ 2 and g(x) = x2 .
o
Find (g f)(­5)
o
Find (g f)(3)
Feb 27­1:38 PM
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7­6 Day 2 Function Operatoins March 02, 2009
Composition of Functions
Let f(x) = x ­ 2 and g(x) = x2 .
o
Find (f g)(­5)
o
Find (f g)(3)
Feb 27­1:38 PM
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7­6 Day 2 Function Operatoins March 02, 2009
Composition of Functions
Let f(x) = 2x, g(x) = x2 + 1 and h(x) = x ­ 6.
o
Find (f g)(1)
o
Find (h g)(5)
o
Find (f h)(2)
o
Find (g h)(­7)
o
Find (h f)(2)
o
Find (f f)(­3)
Feb 27­1:38 PM
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7­6 Day 2 Function Operatoins March 02, 2009
Composition of Functions
Let f(x) = 2x, g(x) = x2 + 1 and h(x) = x ­ 6.
o
Find (f g)(x)
o
Find (h f)(x)
Feb 27­1:38 PM
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7­6 Day 2 Function Operatoins March 02, 2009
Critical Thinking:
Is a composition of functions commutative? Explain.
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7­6 Day 2 Function Operatoins March 02, 2009
Real World Connections
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7­6 Day 2 Function Operatoins March 02, 2009
b. Use a composition of your two functions to model how much you would pay for an item if the clerk applies the discount first and then the coupon.
c. Use a composition of your two functions to model how much you would pay for an item if the clerk applies the coupon first and then the discount.
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7­6 Day 2 Function Operatoins March 02, 2009
d. How much more is any item if the clerk applies the coupon first?
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7­6 Day 2 Function Operatoins March 02, 2009
Homework p. 401
#22­42 even, 43, 63­68
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