O D. 4 [sin 430 - sin 79] https://theorem.nebraska.edu/courses/MTHH044059/unit-3/unit-3-evaluation 18/20 7/7/2021 Precalculus: Trigonometry - Theorem 45. Express this algebraic sum as a product: cos 42 + cos 180 A. -2 sin 30 sin 12 O B. 2 sin 30 sin 120 O C. 2 cos 30 cos 12' O D. -2 COS 30 COS 120 46. Express this algebraic sum as a product: sin 36 - sin 320 A. -2 cos 340 sin 20 B. 2 cos 340 sin 20 c. 2 sin 34 cos 20 O D. -2 sin 340 cos 20 47. Find the value of this expression: sin 45 sin 15 . The second step = O A. [sin 600 - sin 309] O B. [cos 600 + cos 309] O c. 4 [sin 600 + sin 309] O D. 4 [-COS 60 + cos 309] 48. What us the value of sin 45 sin 150 2 O A. V3 + 1 4 O B. V3-1 4 O c. =1- V3 O D. 1- V3 4 https://theorem.nebraska.edu/courses/MTHH044059/unit-3/unit-3-evaluation 19/20 7/7/2021 Precalculus: Trigonometry - Theorem 49. Find the value of this expression: cos 75 - cos 150 . The second step = A. -2 cos 45 cos 30 B. -2 sin 450 sin 30 O c. 2 sin 450 cos 30 O D. 2 cos 450 sin 30 50. cos 75 - cos 150 . The value = O A. 2 O B. V2 2 O c. - VB 2 O D. V2