SOLUTION: If {{{sin A=4/5}}} and A is in the first quadrant, find {{{cos(A/2)}}} and {{{tan(A/2)}}}

Algebra ->  Trigonometry-basics -> SOLUTION: If {{{sin A=4/5}}} and A is in the first quadrant, find {{{cos(A/2)}}} and {{{tan(A/2)}}}      Log On


   

Question 882824: If sin+A=4%2F5 and A is in the first quadrant, find cos%28A%2F2%29 and tan%28A%2F2%29
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
If sin+A=4%2F5 and A is in the first quadrant, find cos%28A%2F2%29 and tan%28A%2F2%29
sinA=4/5
cosA=3/5
..
cos(A/2)=
sin(A/2)=
tan(A/2)=sin(A/2)/cos(A/2)=√(1/4)=1/2