Use the Half-angle Formulas to find the exact value of the trigonometric function. cos 165°
A. - 
B. 
C. - 
D. 
Answer: A
You might also like to view...
Provide an appropriate response.Solve: 2 + 
= 4x
Fill in the blank(s) with the appropriate word(s).
Provide an appropriate response.Consider determining how many possible phone numbers are in an area code (repeated numbers allowed). Is this a combination, a permutation, or neither?
A. Permutation B. Neither C. Combination
Expand.
6
A. x3 + 6x2 + 15x +15x-1 + 6x-2 + x-3 B. x3 + 6x2 + 15x + 20 +15x-1 + 6x-2 + x-3 C. x3 + 6x2 - 15x + 20 -15x-1 + 6x-2 - x-3 D. x3 - 6x2 + 15x - 20 +15x-1 - 6x-2 + x-3
Solve the problem.The beacon on a lighthouse 40 m from a straight shoreline rotates twice per minute. Find dx/dt where x is the distance along the shoreline from the point on the shoreline closest to the lighthouse and the point where the beam hits the shoreline.[Hint: Find an equation relating ? and x where ? is the angle between the beam of light and the line from the lighthouse to the shoreline. Use the chain rule and express d?/dt in radians per minute.]
A. 
= 160? sec ? tan ?
B. 
= 160? sec2?
C. 
= 40 sec2?
D. 
= -160? csc2?