If \( \sin x=-\frac{1}{7}, x \) in Quadrant IV, then find (without finding \( x \) ) : \( \sin (2 x)=\square \) \( \cos (2 x)=\square \) \( \tan (2 x)=\square \)

22. Find the exact value of \( \sin (A+B) \), given \( \sin A=-\frac{4}{5}, A \) is in Quadrant \( I I I, \tan B=\frac{15}{17} \) and \( B \) is in Quadrant \( I \).

Solve, triangle \( A B C \) in which \( a=72.5, \angle B=60^{\circ}, \angle C=83^{\circ} \)

GW Score: \( 12 \%, 6 \) of 50 points A ship is sailing due north. At a certain point, the bearing of a lighthouse 4.9 km away is \( \mathrm{N} 38.5^{\circ} \mathrm{E} \). Later on, the captain notices that the bearing of the lighthouse has become \( \mathrm{S} 33.2^{\circ} \mathrm{E} \). How far did the ship travel between the two observations of the lighthouse?

49. Hisoblang: \( 8 \cos \frac{\pi}{7} \cdot \cos \frac{4 \pi}{7} \cdot \cos \frac{5 \pi}{7} \) A) -1 B) 4 C) 1 D) 2

What is the definition of the cosine function in relation to a right triangle using the adjacent side and hypotenuse?