October 14, 2011 Ms. Wu says … find your new seat! 1.Copy homework into planner. 2.Get your HW 1.15 out. 3.Work on the warm up in pen. 4.Grade HW 1.15 (key is on table). ________________________________________________ Once you’re done with the warm up, place it in the manila folder.

Vocabulary – Compound inequality: an inequality that consists of two separate inequalities joined by and or or. – Conjunction: a compound inequality with and in which the graph is the intersection of the graphs of the inequalities Find values of the variable for which both inequalities are true – Disjunction: a compound inequality with or in which the graph is the union of the graphs of the inequalities. Find values of the variable for which either one or both of the inequalities are true are disjunctions

Relations and Functions

What’s a relation? {(0,0), (2,1), (4,2)} y = 2x Relation: a set of ordered pairs

What’s a function? Domain Range Function: a relation where each value of the domain has exactly one corresponding member of the range Each x has one y Each input has 1 output

Function Mapping 4 Is this a function? How about now?

Sets of Coordinate Pairs Which of the following sets of points represent functions? ( 1, 4 ); ( 2, 6 ); ( 3, 8 ); ( 4, 10 ) ( 1, 3 ); ( 2, 3 ); ( 3, 3 ); ( 4, 3 ) ( -1, 8 ); ( -1, 9 ); ( -1, 10 ); ( -1, 11 ) ( 1, 1 ); ( 2, 5 ); ( 1, 3 ); ( 4, 6 ) ( 0, 4 ); ( -1, 6 ); ( 2, 3 ); ( 0, 4 )

Tables Which of the following tables represent functions? xyxyxy

Scatter Plots Which of the following scatter plots represent functions?

Graphs Which of the following graphs represent functions?

Domain and Range Domain = { all reals} Range = { all reals}

Domain = { all reals} Range = { -3 < y < 3 }

Find the domain and range for the function. Write a rule for the function represented by the graph.

Vertical Line Test A test used to see if a graph is a function. If a graph is a function, a vertical line “sweep” will not intersect the graph more than once.

Is this a function?

What is function notation? f(x) = x + 2 – Pronounced “f of x” – Interchangeable with “y = “ Why use it? – To restrict the domain The domain of f(x) is {3, 4, 5}. Find the range when f(x) = x + 2. Range = {5, 6, 7}

Announcements – Quiz corrections: this time gave 50% if missed a few … next time if any correction is incorrect, you will not receive any points back. – Re-take postponed until Thursday, 10/20 In order to make an appointment to re-take the test for up to a 90%, you must first show me completed test corrections. Appointments are made either via or a note Unit 1.2 Test grade will be the first test grade of 2 nd nine weeks All students who want to re-take are advised to attend tutorials this Thursday All work must be turned in by Wed, 10/12