SOLUTION: prove that: sin(90+x)*cosx*tan(-x)/cos(180-x)=sinx

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Question 1081011: prove that:
sin(90+x)*cosx*tan(-x)/cos(180-x)=sinx
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
sin(90+x)*cosx*tan(-x)/cos(180-x) = sinx
sin(90+x) = cos(x)
tan(-x) = -tan(x)
cos(180-x) = -cos(x)
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cos*cos*(-tan)/(-cos) = cos*tan = cos*(sin/cos) = sine
with restrictions.