Functions Domain and Range Review Find the domain

Functions: Domain and Range

Review: Find the domain and range of the function: Domain: {list all x values in table} in numeric order without listing repeats Range: {list all y values in table} in numeric order without listing repeats x 3 5 6 f(x) 5 -2 -4 10 12 -15 Domain: {3, 5, 6, 10, 12} Range: {-15, -12, -4, -2, 5} x 0 -9 3 f(x) 10 8 10 4 -12 -5 -15 This is the same as Domain: {0, -9, 3, 4, -12} Range: {10, 8, 10, -5, -15} you might see it written this way sometimes but numeric order is better Domain: {-12, -9, 0, 3, 4} Range: {-15, -5, 8, 10}

Find the domain of the function:

Find the domain of the relation: Domain: {all real numbers} Even though you can’t see all x values of this function from the graph, it will go on forever in each direction (we will learn more about identifying that later) Domain: {x > 0} Domain: {-2 < x < 2} This is NOT a function, but the relation still has a domain and range Domain: {all integers} Notice this ends up being a discrete graph

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: Range: {6, 8, 9, 10, 11} {72, 74, 76, 78, 82}

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: Will {whole numbers ≥ 0} the graph of this be discrete or continuous? Discrete!

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. 2 x 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 substituting 50 in where f(x) is. 50 = 0. 2 x x = 250 You cannot go over 250 texts. Can So the largest amount you can have is 250 you have negative text messages? Write the domain. Domain: {0 ≤ x ≤ 250} No, so the smallest amount you can have is 0