Math 131 Week in review 1 I. Classify each function as a power function, a polynomial, a rational function, or an exponential function and find f(a) for the given a. a ) f ( x ) 5 (3 ) a2 c) g ( x) 6 3 x a 8 x b) f ( x) 4 x d ) h( x) e ) K ( x ) 18 x 24 x 32 5 a2 3x 5 x 9x 4 2 a 1 a 2 3 II. What are the domain and range of a function? Find the domain and range of each function. a) f ( x) x2 b) f ( x) x 1 2 c) f ( x) x 1 2 WIR d) g ( x) x x 3x 4 2 1. A box will be made from a 50 inch by 20 inch cardboard by cutting equal size squares from the corners. Describe the volume of the box as a function of the side of the square cutouts. 2. Simplify the difference quotient f ( x h) f ( x) h 2 for f ( x ) x 3 x . 3. A box has a rectangular base with length equal to twice the width. The height of the box is 1.5 times the length. Describe the volume as a function of the width. f ( x) 4. Find the domain of a ) 2 x 3x 2 b) 1 g ( x) 16 x 2 25 x 5. Graph the piecewise function f ( x ) 2 5 x0 0 x 3x What is the domain of f? Where is f increasing? Where is f decreasing? 6. Determine whether or not the points are collinear? What is the least squares best fitting line? Are any of the original points on the least squares line? a) (-3, 4) (0,1) (2, -2.5) b) (0, 1) (1, 3) (2, 4.2) (3, 5.6) 7. Factor each quadratic and find any roots or state no roots exist. 2 a) y x 3x 2 d) y x 6 x 10 2 y 2x 3x 2 b) 2 e) c) 2 y 9 x 12 x 5 2 y 16 x 8 x 1 8. Find the degree and leading term and leading coefficient of each polynomial. a) 7 24 x 4 x 3 b) 8 5 x 7 x 90 9. For y 4 x 5 , a) if x increases by 1 unit then y___________. b) if x decreases by 2 units the y___________. c) if y increases by 3 units then x______________. 10. A tree is 2.4 ft tall when planted. It’s height increases by 50% the first year and increases by 70% the second year. a) Describe the height of the tree using a piecewise linear model. b) Use quadratic regression to find a quadratic model. What does the value of r 2 tell you in this case? 11. An object is shot upward into the air with velocity v ( t ) 20 10 t cm./sec where t is in seconds. When is the velocity positive, 0, negative? When is the height increasing, stationary, decreasing? 12. Each function is a transformation of a basic function. Give the basic function and list the transformations in a proper order that result in the given function. a) f ( x) 2 x 5 6 b) f ( x ) 2 cos( x ) 4 c) f ( x ) ( x 2 )( x 6 ) d) f ( x ) 15 x 2 x 2