answer it all with solutions / explanations
Intro- Functions Functions, Function Notations, and Equations Choose the correct answer. Write it on your answer sheet. 1. It is an equation in two variables x and y, where the variable y may be expressed as f(x) if every value of x corresponds to a single value of y. a. function b. equation c. variable d. notation 2. How will you read x->2x+5? . x is mapped to 2x+5 c. from x to 2x+5 b. x approaches 2x+5 d. x can be written as 2x+5 3. Which of the following is not a function? a. 5x+2 b. y=12x+5 c. f(x)=3x+1 d. s=7t+9 4. Elaine bought a cake-making kit. She sells one-pound cakes for P75 each. Write a function C that shows how much she earns selling p pounds of cake. a. C(p)=75p C(p)=75p+150 b. C(p)=75+p d. C(p)=75p+150+p 5. A rectangular garden has a perimeter of 120 m. Express its area A as a function of the width w. a. A(w)=60w-w2 C. A(w)=120w-120w2 b. A(w)=60w-60w2 d. A(w)=120w=w2 Functions vs Relations Choose the correct answer. Write it on your answer sheet. 6. It is a set of numbers grouped with each other that may or may not represent a pattern. a. relation c. correspondence b. function d. ordered pairs 7. Which of the following graphs represents a relation that is a function? 8. Which of the following relations is a function? a. {(-4,3),(-4,2),(1,9),(6,7)} C. {(2,1),(4,2),(2,3),(8,4)} b. {(-4,3),(-2,0),(2,7),(3,9)} d. {(0,0), (0,1),(2,3),(4,5)) 9. Which of the following relationships is not an example of a real-life function? a. people and their siblings parents and their firstborn children b. people and their mothers d. people and their fathers 10. Categorize the following relationships according to whether they are functions or not. a. time spent traveling and distance traveled on an airplane flight b. number of hours spent working in a week and amount of money earned that week number of games played by a basketball team and number of games they won d. names of pet owners and names of their petsEvaluating and Graphing Functions Choose the correct answer. Write it on your answer sheet. 11. How do we evaluate a function? a. by substituting the given value of the variable and simplifying b. by finding the value to be substituted to the variable C. by solving for the value of the variable that will make the function equal to 0 d. by graphing the function on the Cartesian plane 12. Evaluate f(x) at x=10. 1 if x 4 a. 249 b. C. 29 d. 1349 13. What is the graph of the function y=x+3? a. b. C. 14. Joy took P550 from her savings to buy materials for a school project, and she returns P25 every week. The amount Joy needs to put back in her savings after w weeks is modeled by the function A(w)=550-25w. How much money does Joy need to save after 9 weeks? a. P325 b. P225 c. P125 d. P425 15. A mobile network charges P300 a month for a calling plan with 400 minutes of consumable calls. After the initial 400 minutes of calls is consumed, the plan charges an additional P7 per minute. Find the amount to be paid for 430 minutes of phone calls under this plan. a. P510 b. P610 c. P410 d. P810 Domain and Range of Functions Choose the correct answer. Write it on your answer sheet. 16. It is the set of all values of y that can be obtained from the possible values of x. 17. What is the domain of f(x)=x2+5x-3? a. the set of real numbers c. the set of rational numbers b. the set of integers d. the set of complex numbers 18. What is the domain of f(x)=4x+3? a. x2-2 b. x>-3 C. XS- d. x
