Answer:
Step-by-step explanation:
Given that angle A is in IV quadrant
So A/2 would be in II quadrant.
sin A = -1/3
cos A = 
(cos A is positive since in IV quadrant)
Using this we can find cos A/2

1 1/3 - 5/6
Find common demoninator which is 6.
Then do 2*1=2.
Now you got 2/6 - 5/6 = -3/6
Simplify:
-3/6=-1/2
Then combined answers.
1 - 1/2 = 1/2
Final answer is 1/2
For the first one a = 2.5. For the second one m = 4. For the third one m = -4
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