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Re: Trigonometric Equation
Posted:
Nov 20, 2006 11:30 AM


By direct verification 2 sin 24 sin 84 = cos 60  cos 108 = 1/2 + sin 18 2 sin 30 sin 54 = sin 54 = cos 36 Note cos 36  sin 18 = 1/2 etc Prasad > How can I prove that x=30 "exactly" is the solution > of the following equation? > > sin(54x) / sinx = sin54 / sin84 > > All I've been able to find is x=arctan[(sin84sin54) / > (sin54 + sin84cos54)] approximately equal to 30 > > Thanks and regards.



