1. Functions in the REAL World

2. 43210 In addition to level 3.0 and above and beyond what was taught in class, the student may: · Make connection with other concepts in math · Make connection with other content areas. The student will be able to understand the concept of a function. - Correctly use function terminology (domain, range, f(x)). - Determine if a relationship given in a table, graph, or words depicts a function. With help from the teacher, the student has partial success with function terminology, function notation and determining if a relation table or graph depict a function. Even with help, the student has no success understanding the concept of a function. Learning Goal for Focus 3 (HS.A-CED.A.1, HS.F-IF.A.1 & 2, HS.F-IF.B.4 & 5): The student will understand the concept of a function and use of function notation.

3. Review: Find the domain and range of the function: xf(x) 35 5-2 6-4 10-12 12-15 xf(x) 010 -98 310 4-5 -12-15 Domain: {3, 5, 6, 10, 12} Range: {5, -2, -4, -12, -15} Domain: {0, -9, 3, 4, -12} Range: {10, 8, 10, -5, -15}

4. Find the domain of the function:

5. Find the domain and range of the function:  The temperature in a house drops 2°F for every hour the air conditioner is on between the hours 6:00 am and 11:00 am. The following is a list of times and temperatures in the house: 6 am, 82°F; 8 am 78°F; 9 am 76°F; 10 am, 74°F, and 11 am, 72°F.  Domain: {6, 8, 9, 10, 11}  Range: {82, 78, 76, 74, 72}

6. Find the domain of the function:  If the function f(n) represents the number of hours required to construct n pizzas at dinner time at the local delivery joint, what domain makes sense?  You can’t make negative pizzas or partial pizzas.  Domain: {whole numbers ≥ 0}

7. Find the domain of the function:  Your cell phone plan charges you $0.20 for each text message you send. Your parents put a cap of $50 on your texting bill each month. If f(x) = 0.2x is the cost of the total number of texts you send per month, what is the domain of the function?  First find the maximum amount of texts you can send each month by substitute 50 in where f(x) is.  50 = 0.2x  x = 250  You cannot go over 250 texts.  Can you have negative text messages?  Write the domain.  Domain: {0 ≤ x ≤ 250}