Posted by CJ on Thursday, January 13, 2011 at 4:33pm.
Find two exact values of sin(cosˉ¹√5/6)

Trigonometry/ Please Help  Reiny, Thursday, January 13, 2011 at 5:01pm
cos^1 (√5/6)
is an angle Ø so that sinØ = √5/6
sketch a rightangled triangle with hypotenuse 6, and opposite side √5
by Pythagoras the adjacent side is √31
then cosØ = √31/6
so sin(cosˉ¹√5/6) = √31/6