sin4x－π/3转化成cos是什么

∵ sin(-π/3) = cos[ π/2 - (-π/3) ] = cos(5π/6) =cos( π - π/6) = -cos(π/6)；转化成 cos函数后，周期不变；∴sin( 4x - π/3) = cos( 4x + 5π/6)或sin( 4x - π/3) = -cos( 4x + π/6) 。