Chapter 11 1. Eliminate the parameter t to find a Cartesian equation of the curve. y 3t 1, x t 7 2. Find an equation for the conic that satisfies the given conditions. Ellipse, foci 1, 5 , length of major axis 8 Select the correct answer. a. x 32 y 2 16 4x 2 y 3. 15 1 b. x2 y 2 1 16 15 c. x 2 y 52 1 16 15 d. e. x 2 y True or False? If the parametric curve x f (t ), y g (t ) satisfies g '(1) 0, then it has a horizontal tangent when t 1. 4. Sketch the parametric curve and eliminate the parameter to find the Cartesian equation of the curve. x cos , y sec , 0 / 2 5. Find d 2 y / dx 2 . x 1 t2 , y t t3 6. Find the points on the curve where the tangent is horizontal. x 2 cos cos2 , y 2 sin sin cos 7. Try to estimate the coordinates of the highest point on the curve x 15tet , y 3tet . Round the answer to the nearest hundredth. 8. Find the polar equation for the curve represented by the given Cartesian equation. x y 2 9. Find equations of the tangents to the curve x 3t 2 1, y 2t 3 1 that pass through the point ( 4 , 3 ). 10. Find the points of intersection of the curves r 2 and r 4 sin . 11. True or False? The exact length of the curve x et e t , y 5 12t , 0 t 6 is 1 12 (e 24 e 12 ) . 2 12. Find the length of the curve. x 3t 2 , y 2t 3 , 0 t 3 13. Find the area enclosed by the curve r 2 9cos5 . 14. The graph of the following curve is given. Find the area that it encloses. r 2 cos 6 15. Find an equation of the ellipse with foci ( 5,0) and vertices ( 3,0) . 16. Find an equation for the conic that satisfies the given conditions. Hyperbola, vertices (3, 0), (-3, 0), asymptotes y = ±2x 17. Write a polar equation in r and of a hyperbola with the focus at the origin, with the eccentricity 6 and the directrix x = - 2. 18. Find the equation of the directrix of the conic. r 6 3 sin Select the correct answer. a. y 6 e. x 2 b. y 3 19. Find the eccentricity of the conic. r 9 2 11 cos c. x 6 d. x3 20. Find the area of the shaded region. r 1 sin 1. Eliminate the parameter to find a Cartesian equation of the curve. x(t ) cos 2 5t , y sin 2 5t 2. Find parametric equations to represent the line segment from (-9, 2) to (7, -8). 3. If a projectile is fired with an initial velocity of v 0 meters per second at an angle above the horizontal and air resistance is assumed to be negligible, then its position after t seconds is given by 1 the parametric equations x v 0 cos t , y v 0 sin t gt 2 , where g is the acceleration of 2 9.8 m/s . 2 gravity ground? 4. Round the result to the nearest tenth. Find an equation of the tangent line to the curve at the point corresponding to the value of the parameter. xe 5. If a gun is fired with 20 and v0 470 m/s when will the bullet hit the t , y t ln t 3 ; t 1 Find the points on the curve where the tangent line is horizontal. x 5(cos cos2 ), y 5(sin sin cos ) 6. Find equations of the tangent lines to the curve x 3t 2 1, y 2t 3 1 that pass through the point (13, 17) . 7. Find the area of the region enclosed by each loop of the curve. x sin t 2 cos t , y 2 2 sin t cos t Select the correct answer. a. e. 8. 5 5 b. 4 5 c. 2 5 5 d. 4 5 5 2 5 5 Set up, but do not evaluate, an integral that represents the length of the parametric curve. 9 x t t 9 , y t 8 / 7 , 3 t 12 8 9. True or False? The exact length of the curve x et e t , y 10 2t , 0 t 6 is (e12 24 e 12 ) / 2 . 10. Find d 2 y / dx 2 . x t sin t , y t cos t 11. Sketch the polar curve. r cos3 12. Find the polar equation for the curve represented by the given Cartesian equation. x y 3 13. Find the points of intersection of the curves r 2 and r 4 sin . 14. Using the arc length formula, set up, but do not evaluate, an integral equal to the total arc length of the ellipse. x 4 sin , y 2 cos 2 15. Find the surface area generated by rotating the lemniscate r 5 cos 2 about the line Select the correct answer. a. L 2 /10 L 5 2 b. e. L 10 2 c. L /10 L 2 2 16. Find the area that encloses the curve. r 11 sin 17. Find an equation of the hyperbola with foci 0, 6 and asymptotes y x / 3 . 18. Find an equation of the parabola with focus 9 / 2, 0 and directrix x 7 / 2 . 19. Find an equation of the ellipse with foci ( 5,0) and vertices ( 3,0) . d. 2 . 20. Write a polar equation in r and of an ellipse with the focus at the origin, with the eccentricity 6 and directrix x 8 . 7 Select the correct answer. a. e. 48 7 6 cos 48 r 1 7 sin r b. r 8 3 2 sin c. r 8 7 6 sin d. r 48 6 7 sin