Functions Section 3'1 SLU Mat 151

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FunctionsSection 3.1 SLU Mat 151
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Section 3.1 Functions

• Def Let A and B be two non-empty sets. A
• Function, say f, from A to B is a rule of
• correspondance that assigns to each element
• in set A exactly one element in B.
• The set A is the domain of f. The set of all
• outputs in the set B is called the range of f.

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Section 3.1 Functions
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Section 3.1 Functions

• The function notation of equations is a
• new way to write an equation.

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Section 3.1 Functions

• To say y 2x 5 is the same as to say
• f(x) 2x- 5.
• To say f(x) x4 3x 8 is the same as
• to say y x4 3x 8.

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Section 3.1 Functions

• Domains of functions using equations
• The domain is the set of all real numbers
• that lead to unique real-number outputs.
• Examples
• y 2x 7
• 2)
• 3)

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Section 3.1 Functions

• 4)
• 5)
• 6)

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Section 3.1 Functions

• Range of a function using its equation
• The range is the set of all outputs y. To
• find the range of a function we can
• solve the equation for x and find out
• what values of y will the function not
• take on.
• Examples Find the ranges of
• y x3, y 1/x, y (x-1)/x

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Section 3.1 Functions

• Using f(x) -2x3 4x -3, find the
• following values
• f(0) e) f(2m)
• f(2) g) f(x - 1)
• f(-3) h) f(2 h)
• f(a) i) Simplify DQ

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Section 3.1 Functions

• Resource
• PreCalculus with Unit-Circle Trigonometry
• by David Cohen

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Section 3.1 Functions

• Resource
• PreCalculus with Unit-Circle Trigonometry
• by David Cohen

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Section 3.1 Functions

• Resource
• PreCalculus with Unit-Circle Trigonometry
• by David Cohen