MATH-1340 HANDOUT 2 (Lesson 2) 1. If f ( x) x 2 x 4 , find f ( 2), f (0), and f (4). 2. If f ( x) x 3 x 2 3 , find f ( 3), f (0), and f (2). 3. If f ( x) x 4 3x , find f (4), f (8), and f (13). x 4. If f ( x) , find f ( 2), f (0), and f (3). x 3 Exercises 5-8: If a and h are real numbers, find: (a) f (a ) (b) f ( a ) (c) f (a ) (d) f (a h) f (a h) f (a) (e) f (a) f (h) (f) , provided h 0 h 5. f ( x) 5 x 2 6. f ( x) 3 4 x 7. f ( x) x 2 x 3 8. f ( x) 2 x 2 3x 7 Exercise 9-12: If a is a positive real number, find: 1 1 (a) g (b) (c) g ( a ) g (a) a 9. g ( x) 4 x 2 10. g ( x) 2 x 5 11. g ( x) 2x 2 x 1 12. g ( x) Exercise 13-20: Find the domain of f . 13. f ( x) 2 x 7 14. 15. f ( x) 17. f ( x) 19. f ( x) 9 x2 x 1 x 4x 3 2x 3 x 2 5x 4 (d) g (a) x2 x 1 f ( x) 8 3 x 16. f ( x) 18. f ( x) 20. f ( x) x 2 25 4x 6 x 13x 5 2 4x 3 x2 4 31. An open box is to be made from a rectangular piece of cardboard having dimensions 20 inches 30 inches by cutting out identical squares of area x 2 from each corner and turning up the sides. Express the volume V of the box as a function of x. 32. An aquarium of height 1.5 feet is to have a volume of 6 ft3. Let x denote the length of the base, and let y denote the width. (a) Express y as a function of x. (b) Express the total number of square feet of glass needed as a function of x. 35. A hot-air balloon is released at 1:00 P.M. and rises vertically at a rate of 2 meters per second. An observation point is situated 100 meters from a point on the ground directly below the balloon. If t denotes the time (in seconds) after 1:00 P.M., express the distance d between the balloon and the observation point as a function of t. Answers: 1. 6, 4, 24 5c. 5a 2 3. 12, 22, 36 5d. 5a 5h 2 7a. a 2 a 3 11a. 4 a2 9b. 2a 2 a 1 13. 19. , 4 (4 , ) 7 2 , 11b. 1 4a 2 a2 1 2a 15. [ 3, 3] 3 2 35. d 2 t 2 2500 5b. 5a 2 5e. 5a 5h 4 7e. a 2 h 2 a h 6 9c. 4a 11c. 5f. 5 7c. a 2 a 3 7b. a 2 a 3 7d. a 2 2ah h 2 a h 3 9a. 5a. 5a 2 2 a a 1 7f. 2a h 1 9d. 2a 11d. 2a 3 2a a2 1 17. All real numbers except 2, 0, and 2 31. V 4 x 3 100 x 2 600 x