1. Math 51 3.6 – Introduction to Functions 1

2. Let’s look at a graph of fuel prices (in $ per liter) over time… 2

3. One way to read this graph is by thinking about inputs and outputs. If you input the year 2000, the output is $0.60 per liter. If you input the year 2012, the output is $1.41 per liter. Notice that each input (year) gives you only one output (pump price). This is an example of a function. 3

4. In general, a function relates each input to only one output. Outputs can be observed (as in the pump price above), or they can be generated. 4

5. For example, suppose you give me any real number, and I square that number. So, give me a 5, and I square it to get 25. Give me a 7, and I square it to get 49. I’m a function, because each input corresponds with one output! Here’s how to write it down mathematically: 5

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19. The ________ of a function is the set of all possible _________. The _______ of a function is the set of all possible _________. 19

20. The ________ of a function is the set of all possible _________. The _______ of a function is the set of all possible _________. 20 domain

21. The ________ of a function is the set of all possible _________. The _______ of a function is the set of all possible _________. 21 inputs domain

22. The ________ of a function is the set of all possible _________. The _______ of a function is the set of all possible _________. 22 inputs domain range

23. The ________ of a function is the set of all possible _________. The _______ of a function is the set of all possible _________. 23 inputs outputs domain range

24. 24 Here is the same function represented in different ways. The domain of the above function is _________. The range of the above function is _________.

25. 25 Here is the same function represented in different ways. The domain of the above function is _________. The range of the above function is _________.

26. 26 Here is the same function represented in different ways. The domain of the above function is _________. The range of the above function is _________.