according to me...the sign should be positive...because 140 lies in second quadrant and sinx in second quadrant is +ve, also, sin x is increasing function and cox x is decreasing function.....therefore..the sign should be positive.
and also
according to calculator
sin 140 = 0.98023965944
cos 140 = -0.197813574
sin 140 + cos 140 = +0.78242608543
Last Activity: 10 Years ago
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