Math 2312.3S7 Precalculus Final Exam Review These questions came from the 4 exams. Work through them once using your notes if necessary. Work through them a second time without using your notes. These are the same type of questions you will see on the final exam. You should only study the concepts on these types of questions. No other concepts will be included. The exam is less than 20 questions. 1. The population, P, in thousands of Rivendell is given by P (t ) a. Find the population at t = 0 and t = 8 months. b. Sketch the graph of the function. c. Find the horizontal and vertical asymptotes. d. What is the meaning of the horizontal asymptote? e. What is the maximum population? 500t where t is in months. 2t 2 9 x 2 4x 5 . Identify all asymptotes and intercepts. x 3 2. Sketch the graph of f (x ) 3. Let f (x ) x 2 1 . Find f-1, algebraically, and graph both functions. 4. Prove that f (x ) 1 x 2 and g (x ) x 2 1 are inverses of each other. 5. Solve the following log2(x2 + x) – log2(x2 – x) = 1. 1 6.Solve e 5x 3 10 4 7. If you invest $2000 at a rate of 12% compounded continuously, how long will it take your money to double? 8. Find the exact solutions of the equation 10cos x 5 2 0 for 0, 2 . 9. Big Dog Snowboard Co. charges $15 for equipment rental plus $35 per hour for snowboarding lessons. Half-Pipe Snowboards, Inc. charges $40 for equipment rental plus $25 per hour for lessons. Write a system of equations and determine the number of hours that the cost of equipment and lessons are the same for each company. 10. Graph 2 periods of the equation y = 2 cos 3(x + ) - 1. State the amplitude, period, vertical and phase shifts, and domain and range. Label graph with all critical information. y = 2 cos 3(x + ) - 1 A:_________ P:__________ EP:_________ CI:_________ VS:_________ PS:_________ Domain:___________ Range:___________ 11. Write two different equations for the graph. 12. Write an equation for an ellipse whose major axis is of length 10 and has foci at (6, 1), (2, 1). 13. A spacecraft is in a circular orbit 150km above the Earth. Once it obtains the velocity needed to escape Earth’s gravity, the spacecraft will follow a parabolic path with the focus at the center of the Earth. Suppose it obtains its escape velocity above the North Pole. Assume the center of the Earth is at the origin and the radius of the Earth is 6400km. Write an equation for the parabolic path of the spacecraft. Note: Application questions will not include any hyperbolas. All other conics are fair game. 14. Put the conic x2 + 4y2 + 4x – 24y + 20 = 0 into standard form, then graph. Identify the vertices, co-vertices, and foci. 15. Write the partial fraction decomposition of the following rational expressions: a. x 1 3x 14x 15 2 b. 3x 1 x2 x 16. A line has parametric equations x = t2 - 4 and y equation by eliminating the parameter. 17. Using exact values only, convert 3, t . Write the resulting rectangular 2 from polar to rectangular form. 6 18. Using exact values only, convert (-1, 1) from rectangular to polar form. 19. Find the center & the radius of the sphere 9x2 + 9y2 + 9z2 – 18x – 36y - 72z + 68 = 0. 20. A high school baseball player hits the ball at a height of 3 feet. The initial velocity for the ball is 75 miles per hour at an angle of 20°. The 6 foot center field fence is 350 feet from home plate. Given the equations and viewing window, will the player hit a home run? (The models for projectile motion are in feet per second) These are the equations of the motion of the ball: The equations for the fence are: x1T = (110cos20o))T Y1T = -16T2 + (110sin(200))T + 3 x1T = 350 y1T = 6 – 3T a. Sketch a basic graph of the situation. Does the player hit a home run? b. Find the time it takes the ball hits the ground. c. What is the maximum height of the baseball, and when does the ball reach this maximum height? d. Adjusting only the minimum angle (guess and check), can the player hit a home run? What is the angle needed? e. Adjusting only the initial velocity (guess and check) can the player hit a home run? What is the initial velocity needed? Note: I will not give you the equations or the window on the test. I will give you the models for the equations. You will have to write the equation, but you will not have to convert the units as I did here. The units will already agree. 21. Determine whether u = <-1, 3, -1> and v = <2, -1, 5> are orthogonal, parallel, or neither. 22. Find the angle between u = <0, 2, 2> and v = <3, 0, -4>. Note: You will have to put the vectors into component form first before finding the angle.