Algebra Lesson 3.14 – 3.16 Name: ___________________________________________ What is a Function Notation? Notation can be defined as a system of symbols or signs that denote elements such as phrases, numbers, words etc. Therefore, function notation is a way in which a function can be represented using symbols and signs. Function notation is a simpler method of describing a function without a lengthy written explanation. Example 1: As a fundraiser, Manuel is selling tickets to the school play. He has already sold $20 worth of tickets and the tickets cost $2.50. Define your variables. Write an equation to model the total amount collected from ticket sales. Let 𝑡 =____________________________ Let C(𝑡) =_________________________ What does C(5) mean in terms of the situation? What does C(9) mean in terms of the situation? Find C(5). Find C(9). What does C(0) mean in terms of the situation? What does C(𝑡) = 50 mean in terms of the situation? Find C(0). Find C(𝑡) = 50. 1 Algebra Lesson 3.14 – 3.16 Example 2: A lawyer’s fee is $180 per hour for his services. Define your variables. Write an equation to model the total charge after h hours of service. Let h=____________________________ Let 𝑓(ℎ) =_________________________ What does 𝑓(5) mean in terms of the situation? What does 𝑓(20) mean in terms of the situation? Find 𝑓(5). Find 𝑓(20). What does 𝑓(0) mean in terms of the situation? What does 𝑓(𝑡) = 6300 mean in terms of the situation? Find 𝑓(0). Find 𝑓(𝑡) = 6300 Will you ever have a negative number as an output? Does 𝑓(𝑡) = −1700 make sense? 2 Algebra Lesson 3.14 – 3.16 Example 3: Given the following functions, for the unknown values. Given 𝑓(𝑥) = 2𝑥 − 5, find the following. a. 𝑓(8) b. 𝑓(𝑥) = −9 c. 𝑓(16) d. 𝑓(𝑥) = 15 e. 𝑓(−4) f. 𝑓(𝑥) = 43 Example 4: Given 𝑔(𝑥) = −7𝑥 + 9, find the following. a. 𝑔(3) b. 𝑔(𝑥) = −19 c. 𝑔(10) d. 𝑔(𝑥) = 0 e. 𝑔(−5) f. 𝑔(𝑥) = 58 3 Algebra Lesson 3.14 – 3.16 Example 5: The Mid-Atlantic Ridge separates the North and South American Plates from the Eurasian and African Plates. The function graphed relates the number of centimeters of spread, 𝑆(𝑡) after t years. What does 𝑆(0) mean in terms of the situation? Find 𝑆(0). What does 𝑆(4) mean in terms of the situation? What does S(8.5) mean in terms of the situation? Find 𝑆(4). Find 𝑆(8.5). What does 𝑆(𝑡) = 6 mean in terms of the situation? What does 𝑆(𝑡) = 14 mean in terms of the situation? Find 𝑆(𝑡) = 6. Find 𝑆(𝑡) = 14. 4 Algebra Lesson 3.14 – 3.16 Example 6: Joshua is driving to the store. The average distance d in miles he travels over t minutes is given by the function 𝑑(𝑡). What does 𝑑(0)mean in terms of the situation? Find 𝑑(0). What does 𝑑(1) mean in terms of the situation? What does 𝑑(5) mean in terms of the situation? Find 𝑑(1). Find 𝑑(5). What does 𝑑(𝑡) = 2 mean in terms of the situation? What does 𝑑(𝑡) = 3.5 mean in terms of the situation? Find 𝑑(𝑡) = 2. Find 𝑑(𝑡) = 3.5. 5 Algebra Lesson 3.14 – 3.16 Example 7: 1 Given 𝑓(𝑥) = 𝑥 + 8, find the following. 3 a. 𝑓(3) b. 𝑓(𝑥) = −12 c. 𝑓(11) d. 𝑓(𝑥) = 0 e. 𝑓(−18) f. 𝑓(𝑥) = 22 Example 8: Given 𝑔(𝑥) = 6𝑥 − 12, find the following. a. 𝑔(3) b. 𝑔(𝑥) = −24 c. 𝑔(10) d. 𝑔(𝑥) = 0 e. 𝑔(−5) f. 𝑔(𝑥) = 90 6