SOLUTION: find the exact value of sin 195

Question 440921: find the exact value of sin 195
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
find the exact value of sin 195
..
Use half-angle formula for sin
sin195=sin(390/2)=+-sqrt(1-cos390)/2) (select negative because sin 195 is in quadrant III where sin is negative.
reference angle for cos 390 in quadrant I is 30 deg or Pi/6 radians
-sqrt(1-cos390)/2)=-sqrt(1-cos30)/2)=-sqrt(1-√3/2)/2)=-sqrt(2-√3/4)=-sqrt(2-√3)/2
sin 195=-sqrt(2-√3)/2 (ans)
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