Name Date Are You Ready For Precalc? ============================================================================= Part 1: No calculators allowed (1–11) You should have transformed parent functions by dilation and translation. 1. Describe verbally and algebraically what transformation was applied to the dashed graph, f, to get the solid graph, g. 4. Explain how to find all asymptotes of a rational function 5. Explain why there cannot be oblique AND horizontal asymptotes when graphing a rational function. 6. Write the general equation for a(n) • Exponential function • Power function Words: Equation: 2. In precalculus you have used angles to measure rotation, so the angles can be greater than 180˚ or negative. Sketch an angle of 210˚ in standard position in a uv-coordinate system. Mark the reference angle and write its measure. Write the exact value (no decimals!) of cos 210˚. • Logarithmic function 7. Sketch the graph of a • Logistic function • Quadratic function 8. Draw and label, from memory, the unit circle including all appropriate measures and labels. 3. You apply transformations to a sinusoid, an example of a periodic function. Sketch one cycle of this sinusoid. Show coordinates of high and low points and upper and lower bounds. (you need to know how each constant in the equation transforms the parent function y = cos y = 5 + 2 cos 3( – 20˚) 9. Suppose that a computer software company has 30 programmers. Use factorials to write the number of different ways they could select a group of 6 of the programmers to work on a particular project. 15. Making a mathematical model involves finding the particular equation. Find an equation for the sinusoid for which a half-cycle is shown here. SCALE IS OFF! 10. Given A and B are independent events with probabilities P(A) = 0.9 and P(B) = 0.8, find the probability that A or B occurs. 11. Given that the probability of event C is 0.3 and the payoff is $10 if C occurs and –$2 if C does not occur, find • P(not C) • The mathematical expectation Part 2: Graphing calculators allowed (12–44) To apply sinusoids to real-world problems, you defined circular functions, with the help of radians. 12. Show how the x-axis is wrapped around the unit circle to define an angle of 2 radians. 16. Dilations and translations have special names when applied to sinusoids. For the graph in Problem 15 give the: • Amplitude • Period • Phase displacement (for cosine) • Sinusoidal axis location Tide Problem (17–20): The depth of water at the seacoast is a periodic function of time due to the motion of the tides. Suppose that the depth y, in feet, is given by y = 3 + 4 cos 5.7 ( x 2) where x is time in hours after midnight last night. 17. At what time did the first high tide occur today? How deep was the water at that time? 18. What is the period of this function? 19. When does the second high tide occur today? 13. How many degrees are there in 2 radians? 14. Write the exact number (no decimals!) of radians in 90˚. 20. The tide is completely “out” when the depth calculated for the water is zero or less. Between what two times is the tide first completely out today? Show how you get your answer. Dog’s Weight Problem (21-24): As dogs of a particular breed grow, their weight is a function of their length. Suppose that these lengths and weights have been measured. x (in.) y (lb) 6 2 12 14 24 98 29 170 34 260 37 330 21. What pattern do the first three data points follow? What type of function has this pattern? 22. Find the particular equation for the function in Problem 21. 23. Use the appropriate kind of regression to find the function of the type in Problem 21 that best fits all six data points. Write the correlation coefficient, and explain how it indicates that the function fits the data quite well. Weight-lifting Problem (25–28): Emma Strong starts an exercise routine to build up her muscles. She measures her progress at the end of each week, x, by the number of pounds, y, she can lift (see the table and graph). x (weeks) 1 2 3 4 5 6 7 y (lb) 14 18 24 31 40 49 60 25. What graphical evidence is there that an exponential function might fit the points? Based on endpoint behavior, why would a logistic function be more reasonable? 26. Write the particular equation of the best-fitting logistic function. Use the equation to predict the weight she can lift after week 15. 24. Use the regression equation from Problem 23 to predict the weight of a newborn puppy 4 inches long. Which do you use, interpolation or extrapolation, to find this? How can you decide? 27. Plot the logistic function. Sketch the result on the given figure. Show the upper horizontal asymptote and the point of inflection. 28. What limit does the number of pounds approach? Flower Pot Problem (29–30): A precalculus class reasons that the height, h, in centimeters, of a stack of flower pots should be a linear function of the number of pots, p, in the stack. They measure the data shown in the table and point plot. FIX SCALE! Logarithmic Function Problems (31–34): 31. Use the definition of logarithm to evaluate y = log7 41. 32. Use the log of a power property to solve this exponential equation: 52x = 157 p (number h (cm) of pots) 1 10.5 2 13.2 3 16.0 4 18.7 5 21.3 6 23.9 7 26.5 8 29.1 9 31.6 10 34.1 29. Write the linear regression equation, and give numerical evidence from the regression result that a linear function fits very well. 30. Use the regression equation to predict the height of a stack of 20 pots. Why is this not twice the height of a stack of 10 pots? 33. Use the change of base property to evaluate log891 using natural logarithms. 34. Plot the graph of f(x) = ln x. Sketch the result. Explain why f(1) = 0. Give numerical evidence to show how f(4) and f(6) are related to f(24).