sin4x－π/3转化成cos是什么

更新时间2022-05-28 11:18:19

∵ 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) 。

诱导公式：sina=cos(π/2-a)

sin(4x-π/3)

=cos[π/2-(4x-π/3)]

=cos(5π/6-4x)