SOLUTION: express sin(-140) as a function of a positive acute angle

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Question 844752: express sin(-140) as a function of a positive acute angle
Answer by lwsshak3(11628) About Me  (Show Source):
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express sin(-140) as a function of a positive acute angle
sin(-140)=sin(220)
Both angles terminate in quadrant III and have the same reference angle of 40˚.
sin(-140)=sin(220)=-sin40˚