<PRE><B>Question 667610</B>
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Cotangent is cosine over sine, so if cosine is positive and cotangent is negative, sine has to be negative.  Cosine is positive in QI and QIV.  Sine is negative in QIII and QIV.  Can you take it from here?


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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