agrawal (aa87823) – HW15 – clark – (55000) This print-out should have 8 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 001 5. 10.0 points C2 2 Ct, t , 12 003 0 ≤ t ≤ 4, is the arc of the parabola 12y = x2 from (0, 0) to (6, 3), find the coordinates of the point P on this arc corresponding to t = 2. 3 3 , 1. P = 2 16 3 2. P = 3 , 4 3 3 3. P = , 2 4 3 , 3 4. P = 4 3 5. P = , 3 16 3 3 , 6. P = 16 2 002 1. 2. 3. 10.0 points Find a Cartesian equation for the curve given in parametric form by x(t) = 2 cos 3t , 4. y(t) = 5 sin 3t . 1. 25x2 − 4y 2 = 100 1 x2 y 2 + = 25 4 100 x2 y 2 1 3. − = 4 25 100 2. 4. 4x2 + 25y 2 = 100 x2 y 2 1 − = 25 4 100 6. 25x2 + 4y 2 = 100 If the constant C is chosen so that the curve given parametrically by 1 5. 6. 10.0 points agrawal (aa87823) – HW15 – clark – (55000) 2 y 2. 004 1 1 x 10.0 points 0 0 1 1 Which one of the following could be the graph of the curve given parametrically by y 3. 1 1 (x(t), y(t)) when the graphs of x(t) and y(t) are shown in x 0 0 1 1 1 1 y 4. 1 1 t 0 0 1 1 x(t) : y(t) : x 0 0 1 1 y 1. 1 y 1 5. 1 1 x 0 0 1 1 x 0 0 1 1 agrawal (aa87823) – HW15 – clark – (55000) 3 y 6. 1 3. (6 cos t, 2 + 6 sin t), 1 0 ≤ t ≤ 2π 4. ( − 6 cos t, 2 − 6 sin t), 0≤t≤π 5. (6 cos t, 2 − 6 sin t), 0 ≤ t ≤ 2π 6. (6 cos t, 2 − 6 sin t), 0≤t≤π x 0 0 1 007 1 005 10.0 points Find parametric equations representing the line segment joining P (−1, 4) to Q(4, −2) as (x(t), y(t)) , 10.0 points A ladder 13 feet in length slides down a wall as its bottom is pulled away from the wall as shown in y 0 ≤ t ≤ 1, where P = (x(0), y(0)) , Q = (x(1), y(1)) and x(t), y(t) are linear functions of t. P 13 1. (−1 + 5t, 4 − 6t) 2. πt πt 4 − 5 sin2 , 4 − 6 cos2 2 2 θ x 3. (4 − 5t, −2 + 6t) 4. (4 − 5t2 , −2 + 6t2 ) 5. πt πt −1 + 5 sin2 , −2 + 6 cos2 2 2 6. (−1 + 5t2 , 4 − 6t2 ) 006 1. (3 cos θ, 10 sin θ) 10.0 points Find the path (x(t), y(t)) of a particle that moves once counter-clockwise around the curve x2 + (y − 2)2 = 36 , starting at (6, 2). 1. (6 cos t, 2 + 6 sin t), 2. ( − 6 cos t, 2 − 6 sin t), Using the angle θ as parameter, find the parametric equations for the path followed by the point P located 3 feet from the top of the ladder. 2. (3 sin θ, 10 cos θ) 3. (3 sec θ, 10 tan θ) 4. (3 tan θ, 10 sec θ) 5. (10 sin θ, 3 cos θ) 0≤t≤π 0 ≤ t ≤ 2π 6. (10 cos θ, 3 sin θ) 7. (10 tan θ, 3 sec θ) agrawal (aa87823) – HW15 – clark – (55000) 8. (10 sec θ, 3 tan θ) 008 10.0 points If a thread is unwound from a stationary circular spool of radius 7, keeping the thread taut at all times, then the endpoint P traces out a curve as shown in y Q P θ x A called the Involute of the circle. Using the fact that P Q has length 7θ, find parametric equations for P using the angle θ as parameter. 1. 7(cos θ − θ sin θ), 7(sin θ + θ cos θ) 2. 7 sin θ − θ cos θ, 7 cos θ + θ sin θ 3. 7(sin θ − θ cos θ), 7(cos θ + θ sin θ) 4. 7 sin θ + θ cos θ, 7 cos θ − θ sin θ 5. 7 cos θ − θ sin θ, 7 sin θ + θ cos θ 6. 7(sin θ + θ cos θ), 7(cos θ − θ sin θ) 7. 7 cos θ + θ sin θ, 7 sin θ − θ cos θ 8. 7(cos θ + θ sin θ), 7(sin θ − θ cos θ) 4