SOLUTION: please show me how to evaluate COS (SIN^-1 1/2)

Algebra ->  Trigonometry-basics -> SOLUTION: please show me how to evaluate COS (SIN^-1 1/2)      Log On


   

Question 575726: please show me how to evaluate
COS (SIN^-1 1/2)
Found 2 solutions by htmentor, solver91311:
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
arcsin(1/2) means an angle whose sine is 1/2.
Sin(30) = 1/2 [in the 1st quadrant], so we have cos(30) = sqrt%283%29%2F2

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


What is the cosine of the angle whose sine is 1/2?

Look on the unit circle, recalling that the -coordinate of the point of intersection of the terminal side ray and the unit circle is the sine of the angle and the -coordinate is the cosine:



The angle whose sine is 1/2 is either in which case or in which case

John

My calculator said it, I believe it, that settles it
The Out Campaign: Scarlet Letter of Atheism