Найдите
sin18°*sin54°
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Ответ:sin54*sin18 = (2cos18*sin18*sin (90-36)) / (2cos18) = (sin36*cos36) / (2cos18) = sin72 / (4cos18) = sin (90-18) / (4cos18) = cos18 / (4cos18) = 1/4

Объяснение: