GRAPH LINEAR FUNCTIONS3.7

FUNCTION NOTATIONEquations that represent functions are often written in function notation.

f(x) is used in place of y in function notation. y = mx + b becomes f(x) = mx + b

If I want to evaluate for a number, I can plug the number in for x

f(#) means to plug the # in for x in order to evaluate.

***can use other letters. For example g(x), h(x),…

EXAMPLEEvaluate the function y = 3x + 2 for x = -2, 0, and 3

X = -2:

X = 0:

X = 3:

EXAMPLEEvaluate the function f(x) = 3x + 2 for x = -2, 0, and 3

X = -2:

X = 0:

X = 3:

EXAMPLEEvaluate when x = 4

f(x) = 3x – 2

g(x) = -2x + 7

h(x) = ½x - 5

EXAMPLEGiven y = 3x + 4, find the value of x so that y = 10

EXAMPLEGiven f(x) = -2x+10, find the value of x so that f(x) = -6

FIND THE VALUE OF X SO THE FUNCTION HAS THE GIVEN VALUE.( ) 2 5; 9f x x 2( ) 6; 14

3g x x ( ) 4 18; 8h x x

c.

PARENT FUNCTIONA family of functions is a group of functions with similar characteristics. For instance, linear functions of the form g(x) = mx + b is a family of functions. The most basic form of this equation is f(x) = x. This is called the parent function.

GRAPH AND COMPARE TO F(X)=X

2( )3

g x x

GRAPH AND COMPARE TO F(X)=X

HOMEWORKpp. 203-204: 3, 7, 11, 15-21 odd, 23, 25, 31, and 33