Trigonometry: Perencevich Chap. 14 Mid-chapter Review Gonzaga College High School 1. Evaluate the six trigonometric functions on the angle θ illustrated below. Give exact- value answers. 7. Find all solutions of the following trigonometric equations in the interval 0 ≤ θ < 2π. Where possible, give exact-value answers. For these equations it will be helpful to recall cos2 θ + sin2 θ = 1 a) cos2 θ + cos θ = sin2 θ b) sin2 θ = cos2 θ c) sin2 θ + 2 cos θ + 1 = 0 d) cos2 θ = −4 sin θ e) 6 cos2 θ − 3.1 cos θ − 2.3 = 0 2. Find the radian measure of the angles whose degree measure is given below. a) 120◦ b) 45◦ c) 210◦ c) 315◦ 3. Give the exact value of the following: a) cos 120◦ b) sin 30◦ c) sin 45◦ d) tan 210◦ e) sin 315◦ f) tan 180◦ 4. Evaluate without a calculator: √ a) cos−1 1/2 b) sin−1 3/2 c) sin−1 (−1/2) √ √ d) tan−1 (− 3) e) sin−1 (−1/ 2) f) tan−1 (−1) 5. Find all solutions of the following trigonometric equations in the interval 0 ≤ θ < 2π. Where possible, give exact-value answers. a) 5 sin θ + 3 = 0 c) 3 sin2 θ − sin θ − 2 = 0 e) tan3 θ = tan θ b) 4 sin2 θ − 2 = 0 d) sin2 θ−2 sin θ−1 = 0 f) 2 sin θ cos θ = cos θ 8. Find four angles θ that have the following angles for a reference angle with 0 ≤ θ < 2π. a) π/5 b) 0.1341 9. Sketch one period of each of the following equations. Give the period, phase angle, and, where appropriate, the amplitude. a) y = 3 sin(2t + π) b) x = 4 cos(3t + π) c) z = tan 3t 10. Give the exact value of the following: 17π 3 25π tan 3 13π 4 19π sin 2 a) cos b) sin c) cos 22π d) e) f) cos 6. If sin θ = 2/3 and π/2 < θ < π, find: a) cos θ b) tan θ c $2012 scp All Rights Reserved 17π 6 Trigonometry: 1. √ sin θ = 2 2/3 √ csc θ = 3/2 2 cos θ = 1/3 √ tan θ = 2 2 sec θ = 3 √ cot θ = 1/2 2 2. a) 2π/3 c) 7π/6 b) π/4 c) 7π/4 3. a) −1/2 b) 1/2 d) 1/ 3 e) − 2/2 √ 4. a) π/3 d) π/3 Perencevich Chap. 14 Mid-chapter Review √ b) π/3 e) −π/4 c) √ 2/2 f) 0 c) −π/6 f) −π/4 5. Find all solutions of the following trigonometric equations in the interval 0 ≤ θ < 2π. Where possible, give exact-value answers. a) θ = 3.7851 b) θ = π/4; θ = 3π/4 θ = 5π/4; θ = 7π/4 θ = 5.6397 c) θ = π/2 d) θ = 3.5687 θ = 3.8713; θ = 5.5535 e) θ = 0; θ = π θ = π/4; θ = 3π/4 θ = 5π/4; θ = 7π/4 θ = 5.8561 f) θ = π/2; θ = 3π/2 θ = π/6; θ = 5π/6 6. If sin θ = 2/3 and π/2 < θ < π, find: √ a) cos θ = − 5/3 √ 7. Find all solutions of the following trigonometric equations in the interval 0 ≤ θ < 2π. Where possible, give exact-value answers. For these equations it will be helpful to recall cos2 θ + sin2 θ = 1 a) θ = π/3; θ = π; θ = 5π/3 b) θ = π/4; θ = 3π/4 θ = 5π/4; θ = 7π/4 c) θ = 2.3921 d) θ = 3.3799 θ = 5.5337 θ = 6.0449 e) θ = 0.3785; θ = 1.9960 θ = 4.2872; θ = 5.9047 8. a) θ = π/5; θ = 4π/5 θ = 6π/5; θ = 9π/5 b) θ = 0.1341; θ = 3.0075 θ = 3.2757; θ = 6.1491 9. a) b) c) See below for the sketches. A = 4; period= π ; ϕ = −π/2 A = 3; period= 2π/3; ϕ = −π/3 period= π/3; ϕ = 0 10. Give the exact value of the following: a) d) 1 2 √ 3 b) tan θ = −2/ 5 9. c $2012 scp All Rights Reserved b) √ − 2 2 e) −1 c) 1 f) √ − 3 2