5-3: Function Rules, Tables, and Graphs

Prof. Annie TranDr. Larry Le

Sir. Tommy Le

Welcome to Lesson 5-3!!

Objectives

To draw graphs and write function rules.

To analyze tables.

To model function rules.

Vocabulary!

Continuous data - data in which numbers between any two values make senses.

•(Includes measurement of temperature, length, or weight)

Discrete data - data that involves in count of items

•(Includes number of people or number of cars)

Eff Exx ?!?!

We write function rule as f(x) = x

f(x) = y value (range, output)

x = x value (domain, input)

•x value can be any numbers.

Examples• Model the function rule: f(x) = -⅓x + 2

using a table of values and a graph.

x f(x) = -⅓x + 2 f(x)

-6 f(x)= -⅓(-6) + 2 4

0 f(x)= -⅓(0) + 2 2

12 f(x)= -⅓(12) + 2 -2

x,f(x)

(-6,4)

(0,2)

(12,-2)

Plot points

Quick Check

Model the rule f(x) = 10x + 5 with the input value = 1 to 5

Write the answer in ordered pair.

Discrete DataAn automatic photo booth charges (C) $3 for a sheet of photo (p). the function rule is C(p) = 3p

p C(p) = 3p (p,C(p))

5 3(5) (5,15)

8 3(8) (8,24)

9 3(9) (9,27)

Continuous DataYou get 27$ for your salary (s) each hour (h) you worked. The function rule is S(h) = 27h

h S(h) = 27h (h,S(h))

8 27(8) (8, 216)

0 27(0) (0,0)

5 27(5) (5,135

Quick Check

1. Your weight on the moon is one sixth your weight on Earth. Say you are 50kg, what is your weight on the moon. M(w) = 1/6w

2. The function c = 4.20t represents the cost of tickets to a NBA basketball game.

How to graph an absolute value

Graph the function y = |x| + 2. Make a table of values.

x y = |x| + 2 [x,y]

-1 |-1| + 2 = 3 [-1,3]

0 |0| + 2 = 2 [0,2]

1 |1| + 2 = 3 [1,3]

How to graph an exponent

Graph the function f(x) = x2 + 3. Make a table of values.

x f(x) = x2 + 3 [x,y]

-2 4 + 3 = 7 [-2,7]

0 0 + 3 = 3 [0,3]

4 16 + 3 = 19 [4,19]

Assignments

Make a table of values and graph.

f(x) = -3x - 2

y = x2 - 7

y = |2x| + 2

GAMETIME!

f(x)=3x+4

x y

6 ?

9 ?

7 ?

touch the best answer

y=22,31,25

y=18,19,20

y=22,31,50

y=18,27,21

y=10,13,11

f(x)=2x+6x y

9 ?

13 ?

16 ?

fill in the blank of the table.

25

2427

34

32

38

36

f(x)=3x-9

choose the best answer for y

x=19

C.48

D.49

F.46

E.51

A.66

B.69

Real-Life Connections

Calculate bank account saving.

Outcome of something

•Example: For every credit you have, you receive 2 points plus a 2 points bonus. f(x) = 2x + 2

Homework time

Go home and do it

Page. 266 #1-5, 15-23.