Section5.2_Function_Notation_Soln.notebook
March 30, 2012
Section 5.2: Properties of Functions ­ Continued
Function Notation:
A function is a rule that takes an input value and gives a unique corresponding output value, (x, f(x)).
Equation to represent a linear function: y = 2x + 3
Function Notation:
f(x) = 2x + 3
If x = 2, then y = 2(2) + 3 = 4 + 3 (2, 7)
= 7
If x = 2, then f(2) = 2(2) + 3
f(2) = 4 + 3
f(2) = 7
The notation f(2) = 7 indicates that the point with coordinates (2, 7)
lies on the graph of f(x).
Ex.
1.
A(r) = πr2, indicates that "A" is the name of the function and "r " is the independent variable.
Write in the following equations in function notation. A) y = 4x ­ 8
B) h = 5x + 15
C) C = 0.05x + 25
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Section5.2_Function_Notation_Soln.notebook
2.
March 30, 2012
Write as an equation in two variables.
A) h(t) = 2t + 13
B) C(n) = 1.15n + 40
3.
Given f(x) = 4x ­ 5, find
A) f(­4)
4.
B) f(6)
Given h(t) = 4t ­ 5, find t when
A) f(t) = ­15
B) f(t) = 9
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Section5.2_Function_Notation_Soln.notebook
5.
March 30, 2012
Evaluate the following.
A)
B)
6.
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Section5.2_Function_Notation_Soln.notebook
7.
8.
March 30, 2012
The perimeter of a rectangle is P = 2l + 2w. If it is known that the length must be 6 ft, then the perimeter is a function of the width. Write this function using function notation. The equation C = 25n + 1000 represents the cost, C dollars,
for a feast following an Arctic sports competition, where n is
the number of people attending.
a) Describe the function. Write the equation in function notation.
b) Determine the value of C(100).What does this number represent?
c) Determine the value of n when C(n) = 5000.What does this number represent?
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