1 = cos2 (x) + sin2 (x) = (eix + e-ix )2 /4 + sin2 (x) = (e2ix + e-2ix )/4 + e2ln(sin(x)) + 1/2
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1 = cos2 (x) + sin2 (x) = (eix + e-ix )2 /4 + sin2 (x) = (e2ix + e-2ix )/4 + e2ln(sin(x)) + 1/2