Function Notation
Function notation ­ an alternate way to show how two variables are related
An alternate way to express the relationship between x and y is to use function notation for the y­variable.
Feb 18­4:52 PM
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Function Notation
Function notation ­ an alternate way to show how two variables are related
The expression on the right is written in function notation. The first part
is not "f times x". It is read "f of x" or "function of x".
When we substitute a value into a function, it looks like this.
It is read "f at 2" or "the function value at 2".
This part of the function notation stays this way exactly. It is what is substituted wherever the variable shows up.
Feb 23­9:38 AM
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Example:
y=4­3x
a)Write y=4­3x in function notation:
f(x)=4­3x
b)Determine f(5):
f(x)=4­3x
f(5)=4­3(5)
f(5)=4­15
f(5)=­11
Feb 23­9:18 AM
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g(x) = 6x2­9 g(2) h(t)= 81t+14 g(0)
Feb 23­9:24 AM
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Function Notation
Function notation ­ an alternate way to show how two variables are related
Examples
Find the independent variable, given the function value.
Find s for r(s) = 341
To find the independent variable, substitute the function value, then solve like any other equation.
Feb 18­4:52 PM
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example: f(x) = 5(x­15) f(x)=20
20=5(x­15)
20=5x­75
20+75=5x
95/5=x
19=x Feb 23­9:45 AM
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Feb 23­4:24 PM
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http://www.scs.sk.ca/hch/harbidge/math%20a30/unit_2/lesson_1/function_notation.htm
http://www.purplemath.com/modules/fcnnot.htm#fcnnotq
http://www.ltcconline.net/greenl/courses/152A/functgraph/relfun.htm
http://www.algebra­class.com/evaluating­functions.html
http://mathmaine.wordpress.com/2010/02/22/function­notation/
http://www.regentsprep.org/Regents/math/algtrig/ATP5/EvaluatingFunctions.htm
http://www.cliffsnotes.com/study_guide/Function­Notation.topicArticleId­38949,articleId­
38911.html
Feb 23­9:35 AM
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