FUNCTIONS

WHAT IS THE DIFFERENCE BETWEEN A FUNCTION AND A RELATION: Functions are a mathematical relation such that each element of a given set (the domain of the function) is associated with an element of another set (the range of the function) **//__without any one input related to more than one different output. __//** There are four different ways to show a fuction graph, mapping, set of points/ ordered pair, and chart. Which ones are functions? A.
 * GRAPHING**

B. C. D.
 * Answers: B,D

MAPPING ** Which ones are functions? B.  ** **Answer: B
 * A.

SET OF POINTS/ ORDERED PAIR ** ** Which ones are funtions? A. (8,9)(7,6)(3,6)(4,6) B. (5,4)(3,8)(2,3)(8,1) C (7,4)(4,3)(6,2)(7,8) Answers: A,B

CHART Which ones are functions? A. B. **

=

 * WHAT IS THE DIFFERENCE BETWEEN f(x) AND y=? F(x) is used when showing the rule for a function. It is the function of x.Numbers can be inputed in place of x  Ex: f(x)=5x–3  f(5)=5(5)–3  f(5)=25–3  f(5)=22  ** ***Note that when using f(x) you can see both the input and output. You can't when using y=. In the example, the input is 5 and the output is 22.*** **   Y= can be used for all equations. It is not limited to functions- like f(x).Ex1  Y= is used in slope intercept form (y=mx+b).Ex2  Ex1: y=3+6x  Ex2: y=1/2x+5  ** **WHAT ARE THE DOMAIN AND THE RANGE? The following has been submitted by Sean Britton and contributed to by Purple Math. The domain and range are the points on a graph in the X and Y axis. Domain being values on the X axis and range being values in the Y axis. The following is a set of points in a graph, can you name the domain and range for each point? {(2,3),(4,9),(6,15)} For example, in the first point, (2,3), 2 would be the domain and 3, the range.** [[image:http://www.geocities.com/TimesSquare/1848/graphG2.jpg]] **For this graph- Domain- {2600,2800,3100,3400,3700,4200,4500,4800,5300,5600} Range- {1950,1955,1960,1965,1970,1975,1980,1985,1990,1993}**=====