Question 237400
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Substitute the definition of *[tex \LARGE \tan\Theta] in terms of *[tex \LARGE \sin\Theta] and *[tex \LARGE \cos\Theta] and the definition of *[tex \LARGE \cot\Theta] in terms of *[tex \LARGE \sin\Theta] and *[tex \LARGE \cos\Theta], and then multiply the two fractions.


You can also use the fact that the cotangent is the reciprocal of the tangent and the sure and certain knowledge that *[tex \LARGE \forall\,a\,\in\,\R,\ a\,\cdot\,\frac{1}{a}\ =\ 1] 



John
*[tex \LARGE e^{i\pi} + 1 = 0]
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