Answer:
Rule 3
Step-by-step explanation:
The values correspond to the equation y=3^x
Step 1: Convert
, which is in radians into degrees. To convert it multiply by 

900/12
75
Step 2: 75 degrees isn't on the unit circle but 45 degrees and 30 degrees is. Since 45 + 30 = 75 you can use the cosine of 45 and 30 to find the exact value
cos45 = 
cos30 =
Step 3: Add the cos45 and cos30 to get cos5pi/12

Hope this helped!
Answer:
Step-by-step explanation:
Measure of second angle = 90° - x°
Answer:
0.28
Step-by-step explanation:
0.28*100=28