Question 1146963
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cos(100°) = -cos(80°) = -0.173648...


cos(260°) = cos(180°+80°) = -0.173648...


cos(260°) = cos(360°-80°) = cos(80°) = 0.17648...


sin(190°) = cos(190°-90°) = cos(100°) = -cos(80°) = -0.173648...
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Answered and solved.