IM1.5.1 Function basics

Fill in the blanks as you listen to your teacher. 1. A function is a rule that takes an _______________, does something to it, and produces an _______________. 

2. ________________ are all around us. For example, your computer is full of functions. When we use our computers, we are providing the computer with ________________ by pressing keys or using the trackpad or mouse; the computer then provides ________________ by displaying letters, moving cursors, opening programs, and many other actions.

3. In mathematics, functions can be rules, formulas, _____________, _____________, tables of values, or even verbal descriptions that relate one set of input numbers to another set of output numbers. We call the input numbers the ____________________ of the function, and the output numbers the ______________________ of the function. 

4. You might be asking yourself right now, “_________________?  We already know how to use equations and formulas and graphs and tables of values. Why do we have to complicate things with this new idea of a _________________?” That’s a really great question, and the answer is that when we call a relationship a function, we are saying something very _____________________ and precise about the way it relates the numbers in the ________________ to the numbers in the __________________. 

5. If we think about the example of a computer being a set of functions, imagine what would happen if the people who made computers weren’t so interested in being _____________________. What if you couldn’t be sure what would happen when you press the “a” key?  What if there were two __________________ things that could happen when you pressed the space bar, and you just had to live with whatever happened?

6. So the thing that makes functions special relationships is that functions always assign ____________________________________________________________________. That way we can be sure what is going to happen when we apply a function to a set of numbers.