Function Notation

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Function Notation

• 3102.3.25  Find function values using f(x)
  notation or graphs.

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What is function notation?

• Function notation is another way to write y
• The notation looks like this f(x)
• f(x) is read f of x

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Solving Problems with Function Notation

• f(x) 2x 5, find f(5)
• f(5) 2(5) 5 Plug in 5 in place of x
• f(5) 10 5 Simplify
• f(5) 15 Simplify
• This also means that when x 5, y 15
• (5,15)

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Try this problem

• f(x) -3x 5, find f(-2)
• f( -2 ) -3( -2 ) 5
• f( -2 ) 6 5
• f( -2 ) 11

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Other forms of Pythagorean Theorem

• Function notation is also expressed as
• g(x), h(x), or s(t)
• They are all used in place of y and you may
  see them in other places!

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Two Functions at One Time

• f(x) 6x 3 g(x) 2x 4
• Find the following
• f(4) 2. g(-1)
• 3. g(3) 4. f(0)

Click here to See this problem worked
Click here to See this problem worked
Click here to See this problem worked
Click here to See this problem worked
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Problem 1

• f(x) 6x 3, find f(4)
• f(4) 6(4) 3
• f(4) 24 3
• f(4) 27

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Problem 2

• g(x) 2x 4, find g(-1)
• g(-1) 2(-1) 4
• g(-1) -2 4
• g(-1) - 6

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Problem 3

• g(x) 2x 4, find g(3)
• g(3) 2(3) 4
• g(3) 6 4
• g(3) 2

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Problem 4

• f(x) 6x 3, find f(0)
• f(0) 6(0) 3
• f(0) 0 3
• f(0) 3