AP Calculus AB Review of Curve Sketching Problems Multiple Choice = class problem = homework problem 1969 #7 For what value of k will y = x a) -4 b) -2 k have a relative maximum at x = -2? x c) 2 d) 4 e) none of these 1969 #17 The graph of y 5x 4 x 5 has a point of inflection at a) (0, 0) only b) (3, 162) only c) (4, 256) only d) (0, 0) and (3, 162) e) (0, 0) and (4, 256) 1969 #21 At x = 0, which of the following is true of the function f defined by f ( x ) x 2 e 2 x ? a) f is increasing b) f is decreasing c) f is discontinuous d) f has a relative minimum e) f has a relative maximum 1969 #30 If a function f is continuous for all x and if f has a relative maximum at (-1, 4) and a relative minimum at (3, -2), which of the following statements must be true? a) b) c) d) e) The graph of f has a point of inflection somewhere between x = -1 and x = 3. f '(-1) = 0 The graph of f has a horizontal asymptote The graph of f has a horizontal tangent at x = 3 The graph of f intersects both axes 1973 #22 Given the function defined by f ( x ) 3x 5 20x 3 , find all values of x for which the graph of f is concave up. a) x > 0 d) x 2 b) 2 x 0 or x 2 e) -2 < x < 2 c) -2 < x < 0 or x > 2 1985 #16 The function defined by f ( x ) x 3 3x 2 for all real numbers x has a relative maximum at x = a) -2 b) 0 c) 1 d) 2 e) 4 1988 #4 The graph of y a) x < 0 5 is concave downward for all values of x such that x2 b) x < 2 c) x < 5 d) x > 0 e) x > 2 1993 #15 (calculator question) For what value of x does the function f ( x ) ( x 2)( x 3) 2 have a relative maximum? a) -3 b) 73 c) 25 d) 7 3 e) 5 2 1993 #21 (calculator question) At what value of x does the graph of y a) 0 b) 1 c) 2 1 1 3 have a point of inflection? 2 x x d) 3 e) at no value of x 1997 #5 The graph of y 3x 4 16x 3 24 x 2 48 is concave down for a) x < 0 b) x > 0 c) x < -2 or x > 23 d) x < 2 3 or x > 2 e) 2 3 x2 1997 #85 (calculator question) If the derivative of f is given by f '( x ) e x 3x 2 , at which of the following values of x does f have a relative maximum value? a) -0.46 b) 0.20 c) 0.91 d) 0.95 e) 3.73 1998 #1 What is the x-coordinate of the point of inflection on the graph of y 13 x 3 5x 2 24 a) 5 b) 0 c) 103 d) -5 e) -10 1998 #19 If f ''( x ) x ( x 1)( x 2) 2 , then the graph of f has inflection points when x = a) -1 only b) 2 only c) -1 and 0 only d) -1 and 2 only e) -1, 0, and 2 only 1998 #79 (calculator question) y = g '(x) y = f '(x) a b a b y = h '(x) a b The graphs of the derivatives of functions f, g, and h are shown above. Which of the functions f, g, or h have a relative maximum on the open interval a < x < b? a) f only b) g only c) h only d) f and g only e) f, g, and h 1998 #89 (calculator question) If g is a differentiable function such that g(x) < 0 for all real numbers x and if 𝑓 ′ (𝑥) = (𝑥 2 − 4)𝑔(𝑥), which of the following is true? a) b) c) d) e) f has a relative maximum at x = -2 and a relative minimum at x = 2 f has a relative minimum at x = -2 and a relative maximum at x = 2 f has relative minima at x = -2 and x = 2 f has relative maxima at x = -2 and x = 2 it cannot be determined if f has any relative extrema FREE RESPONSE 1985 #6 y = f '(x) -3 -2 -1 1 2 3 Note: This is the graph of the derivative of f, not the graph of f. The figure above shows the graph of f ', the derivative of a function f. The domain of the function f is the set of all x such that –3 x 3. (a) For what values of x, -3 < x < 3, does f have a relative maximum? A relative minimum? Justify your answer. (b) For what values of x is the graph of f concave up? Justify your answer. (c) Find all points of inflection on the graph of f. (d) Use the information found in parts (a) and (b) and the fact that f (-3) = 0 to sketch a possible graph of f. -3 -2 -1 1 2 3 1992 #1 Let f be the function defined by f (x) = 3x5 – 5x3 + 2. (a) On what intervals is f increasing? (b) On what intervals is the graph of f concave upward? (c) Write the equation of each horizontal tangent line to the graph of f. 1991 #5 Let f be a function that is even and continuous on the closed interval [-3, 3]. The function f and its derivatives have the properties indicated in the table below. x 0 0<x<1 1 1<x<2 2 2<x<3 f (x) 1 Positive 0 Negative -1 Negative f '(x) Undefined Negative 0 Negative Undefined Positive f ''(x) Undefined Positive 0 Negative Undefined Negative (a) Find the x-coordinate of each point at which f attains an absolute maximum value or an absolute minimum value. For each x-coordinate you give, state whether f attains an absolute maximum or an absolute minimum. (b) Find the x-coordinate of each point of inflection on the graph of f. Justify your answer. (c) In the xy-plane provided below, sketch the graph of a function with all the given characteristics of f. 1 -3 1 -1 -2 2 3 -1 1993 #5 (calculator question) (1, 1) 1 Note: this is the graph of the derivative of f, not the graph of f 1 2 The figure above shows the graph of f ', the derivative of f. The domain of f is the set of all x such that 0 < x < 2. a) Write an expression for f '(x) in terms of x. b) Given that f (1) = 0, write an expression for f (x) in terms of x. c) In the xy-plane provided below, sketch the graph of y = f (x). 2 1 -2 1 -1 -1 -2 2 1996 #1 Note: this is the graph of the derivative of f, not the graph of f -3 1 -1 -2 2 4 3 5 The figure above shows the graph of f ', the derivative of a function f. The domain of f is the set of all real numbers x such that –3 < x < 5. (a) For what values of x does f have a relative maximum? Why? (b) For what values of x does f have a relative minimum? Why? (c) On what intervals is the graph of f concave upward? Use f ' to justify your answer. (d) Suppose that f (1) = 0. In the xy-plane provided, draw a sketch that shows the general shape of the graph of the function f on the open interval 0 < x < 2. 1 2 2000 #3 -7 -6 -5 -4 -3 -2 -1 1 2 3 4 5 6 7 The figure above shows the graph of f ', the derivative of the function f, for -7 ≤ x ≤ 7. The graph of f ' has horizontal tangent lines at x = -3, x = 2, and x = 5, and a vertical tangent line at x = 3. a) b) c) d) Find all values of x, -7 < x < 7, at which f attains a relative minimum. Justify your answer. Find all values of x, -7 < x < 7, at which f attains a relative maximum. Justify your answer. Find all values of x, -7 < x < 7, at which f ''(x) < 0. At what value of x, -7 ≤ x ≤ 7, does f attain its absolute maximum? Justify your answer. 2002 #4 (0, 3) (-2, -3) (2, -3) The graph of the function f shown above consists of two line segments. Let g be the function 𝑥 given by 𝑔(𝑥) = ∫0 𝑓(𝑡)𝑑𝑡. a) Find g (-1), g '(-1) and g ''(-1) b) For what values of x in the open interval (-2, 2) is g increasing? Explain your reasoning. c) For what values of x in the open interval (-2, 2) is the graph of g concave down? Explain your reasoning. d) On the axes below, sketch the graph of g on the closed interval [-2, 2]. 2 2003 #4 (-3, 1) -3 1 -2 1 -1 2 3 4 -1 -2 (4, -2) Let f be a function defined on the closed interval -3 ≤ x ≤ 4 with f (0) = 3. The graph of f ', the derivative of f, consists of one line segment and a semicircle, as shown above. a) On what intervals, if any, is f increasing? Justify your answer. b) Find the x-coordinate of each point of inflection on the graph of f on the open interval -3 < x < 4. Justify your answer. c) Find an equation for the line tangent to the graph of f at the point (0, 3). d) Find f (-3) and f (4). Show the work that leads to your answers. 2004 #5 (-3, 2) The graph of the function f shown to the right consists of a semicircle and three line segments. Let g be the function given by 𝑥 𝑔(𝑥) = ∫−3 𝑓(𝑡)𝑑𝑡. (0, 1) (2, 1) (4, -1) (-5, -2) a) Find g(0) and g '(0). b) Find all values of x in the open interval (-5, 4) at which g attains a relative maximum. Justify your answer. c) Find the absolute minimum value of g on the closed interval [-5, 4]. Justify your answer. d) Find all values of x in the open interval (-5, 4) at which the graph of g has a point of inflection. 2005 #4 Let f be a function that is continuous on the interval [0, 4). The function f is twice differentiable except at x = 2. The function f and its derivatives have the properties indicated in the table below, where DNE indicates that the derivatives of f do not exist at x = 2. x 0 0<x<1 1 1<x<2 2 2<x<3 3 3<x<4 f -1 negative 0 positive 2 positive 0 negative f' 4 positive 0 positive DNE negative -3 negative f '' -2 negative 0 positive DNE negative 0 positive a) For 0 < x < 4, find all values of x at which f has a relative extremum. Determine whether f has a relative maximum or a relative minimum at each of these values. Justify your answer. b) On the axes provided, sketch the graph of a function that has all the characteristics of f. 𝑥 c) Let g be the function defined by 𝑔(𝑥) = ∫1 𝑓(𝑡)𝑑𝑡 on the interval (0, 4). For 0 < x < 4, find all values of x at which g has a relative extremum. Determine whether g has a relative maximum or a relative minimum at each of these values. Justify your answer. d) For the function g defined in part (c), find all values of x, for 0 < x < 4, at which the graph of g has a point of inflection. Justify your answer.